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Income Taxes - Unrecognized Tax Benefits Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Schedule of reconciliation of unrecognized tax benefits activity [Roll Forward]
Unrecognized Tax Benefits – Beginning	$ 408	$ 209
Gross decreases – tax positions in prior period	(5)	(16)
Gross increase – current-period tax positions	21	215
Unrecognized Tax Benefits – Ending	$ 424	$ 408

Commitments and Contingencies - Summary of Lease Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Lease expense:
Operating lease expense	$ 145	$ 141
Total lease expense	145	141
Cash payment information:
Operating cash used for operating leases	180	141
Total cash paid for amounts included in the measurement of lease liabilities	$ 180	$ 141

Loss per Share

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Earnings Per Share [Abstract]

Loss per Share

Basic per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period increased to include, if dilutive, the number of additional common shares that would have been outstanding as calculated using the treasury stock or

if-converted

method, as applicable. The

Pre-Funded

Warrants were included in the weighted average shares outstanding calculation (as of the beginning of the period or the date of the grant, whichever was earlier) for basic and dilutive earnings per share given their nominal exercise price.

The March 2025 Series A Warrants and March 2025 Series B Warrants (and for the period in which the February 2025 Warrants, Funding Notes, and Exchange Notes, as defined in Note 13, were outstanding) were participating securities because holders of such instruments would participate in the event a dividend is paid on common stock, however such holders did not have a contractual obligation to share in the Company’s losses. As such, losses were attributed entirely to common stockholders.

The following table sets forth the computation of basic and diluted net loss per share of common stock for the periods indicated, in thousands except share and per share data:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2025			2024			2025			2024
Basic and diluted net loss per common share calculation:
Net loss	$	(4,423	)	$	(2,874	)	$	(16,673	)	$	(9,075	)
Change in fair value of derivative instruments		—			—			—			(5,047	)

Net loss attributable to common stockholders – basic		(4,423	)		(2,874	)		(16,673	)		(14,122	)
Weighted average common stock outstanding – basic		107,428,969			7,855,763			57,845,406			6,232,123
Net loss per share of common stock – basic	$	(0.04	)	$	(0.37	)	$	(0.29	)	$	(1.46	)
Weighted average common stock outstanding – diluted		107,428,969			7,855,763			57,845,406			8,452,338
Net loss per share of common stock – diluted	$	(0.04	)	$	(0.37	)	$	(0.29	)	$	(1.67	)

The following table provides a summary of instruments where underlying shares issuable upon exercise or conversion were excluded from the diluted loss per share calculation for the periods presented because their

effect would be anti-dilutive. Additionally, the shares underlying the February 2025 Warrants, Funding Notes and Exchange Notes, each outstanding during the nine months ended September 30, 2025, were excluded from diluted loss per share as their effect would be anti-dilutive.


	As of September 30,
	2025		2024
Outstanding stock options		11,272,863		598,540
Outstanding restricted stock units		2,823,857		—
Preferred stock		28,190		28,190
Outstanding warrants (Note 13)		3,141,993		706,674

Total		17,266,903		1,333,404

5. Loss per Share

The shares of the Company’s common stock underlying the

pre-funded

warrants described in Note 15, are included in the weighted average outstanding common stock in the calculation of basic and diluted net loss per share. The Company considers Series A Warrants, and Series B Warrants to be participating securities, because holders of such instruments participate in the event a dividend is paid on common stock. The holders of the Series A Warrants and Series B Warrants do not have a contractual obligation to share in the Company’s losses. As such, losses are attributed entirely to common stockholders.

The following table sets forth the computation of basic and diluted net loss per share of common stock for the periods indicated, in thousands except share and per share data:


	For the Year Ended December 31,
	2024			2023
Basic and diluted net loss per share of common stock calculation:
Net loss	$	(12,978	)	$	(13,316	)
Change in fair value of warrants		(5,047	)		—

Net loss attributable to common stockholders - diluted	$	(18,025	)	$	(13,316	)

Weighted average shares of common stock outstanding - basic		6,640,251			3,140,925
Net loss per share of common stock - basic	$	(1.95	)	$	(4.24	)
Weighted average shares of common stock - diluted		7,700,774			3,140,925
Net loss per share of common stock - diluted	$	(2.34	)	$	(4.24	)

The following were excluded from the diluted loss per share calculation for the periods presented because their effect would be anti-dilutive:


	For the Year Ended December 31,
	2024		2023
Outstanding stock options		598,540		140,109
Preferred stock		28,190		28,190
Outstanding warrants		7,183,064		142,733

Total		7,809,794		311,032

Organization and Basis of Presentation	9 Months Ended	12 Months Ended
Organization and Basis of Presentation	Sep. 30, 2025	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation Description of Business Plus Therapeutics, Inc. (the “Company”) is a clinical-stage pharmaceutical company focused on the development, manufacture and commercialization of complex and innovative treatments for patients battling cancer and other life-threatening diseases. CNSide Diagnostics, LLC is a wholly owned subsidiary of Plus Therapeutics, Inc. that develops and commercializes proprietary laboratory-developed tests, such as the CNSide ™ Test, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. Basis of Presentation The accompanying unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2025 and 2024 have been prepared in accordance with accounting principles generally accepted in the United States of America (“US GAAP”) for interim financial information. Accordingly, they do not include all of the information and footnotes required by US GAAP for annual financial statements. The condensed consolidated balance sheet at December 31, 2024 has been derived from the audited consolidated financial statements at December 31, 2024, but does not include all of the information and footnotes required by US GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation of the financial position and results of operations of the Company have been included. Operating results for the three and nine months ended September 30, 2025 are not necessarily indicative of the results that may be expected for the year ending December 31, 2025.	1. Organization and Operations The Company Plus Therapeutics, Inc. is a clinical-stage pharmaceutical company focused on the development, manufacture and commercialization of complex and innovative treatments for patients battling cancer and other life-threatening diseases. CNSide Diagnostics, LLC is a wholly owned subsidiary of Plus Therapeutics, Inc. that develops and commercializes proprietary laboratory-developed tests, such as the CNSide ™ Test, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. Certain Risks and Uncertainties The Company’s prospects are subject to the risks and uncertainties frequently encountered by companies in the early stages of development and commercialization, especially those companies in rapidly evolving and technologically advanced industries such as the biotech/medical device field. The Company’s future viability largely depends on its ability to complete development of new products and receive regulatory approvals for those products. No assurance can be given that the Company’s new products will be successfully developed, regulatory approvals will be granted, or acceptance of these products will be achieved. Going Concern The Company incurred net losses of $13.0 million for the year ended December 31, 2024, and as of December 31, 2024, the Company had an accumulated deficit of $493.5 million and cash and cash equivalents of $76,000 and short term investments of $3.5 million. Additionally, the Company used net cash of $10.6 million to fund its operating activities for the year ended December 31, 2024. The Company had an outstanding balance of $3.3 million under its line of credit facility (Note 9). The Company expects that its research and development expenditures will increase in absolute dollars in 2025 and beyond. These factors raise substantial doubt about the Company’s ability to continue as a going concern. As disclosed in more detail in Note 15 and Note 18, the Company has entered into various financing agreements and raised capital by issuing its common stock. Nasdaq Listing Compliance On March 8, 2024, the Company received a written notice (the “Notice”) from the Listing Qualifications staff of Nasdaq, notifying the Company that it no longer complied with the requirement under Nasdaq Listing Rule 5550(b)(1) to maintain a minimum of $2.5 million in stockholders’ equity (the “Minimum Stockholders’ Equity Requirement”) for continued listing on The Nasdaq Capital Market or the alternative requirements of having a market value of listed securities of $35 million or net income from continuing operations of $500,000 in the most recently completed fiscal year or two of the last three most recently completed fiscal years. On September 5, 2024, Nasdaq notified the Company that it had not regained compliance with Nasdaq Listing Rule 5550(b)(1). The Company requested a hearing before the Nasdaq hearing panel (“Panel”), and on October 30, 2024, the Company received a decision from the Panel, notifying the Company that it had until March 4, 2025, to demonstrate compliance with the Minimum Stockholders’ Equity Requirement. The Company regained compliance with the Minimum Stockholders’ Equity Requirement in connection with the private placement entered into on March 4, 2025, as described in more detail in Note 18, Subsequent Events. Pursuant to Nasdaq Listing Rule 5815(d)(4)(B), the Company will be subject to a Mandatory Panel Monitor until March 7, 2026. If the Nasdaq Listing Qualifications staff (the “Staff”) finds the Company again out of compliance with the Minimum Stockholders’ Equity Requirement before that date, the Company would not be permitted to provide the Staff with a plan of compliance with respect to that deficiency and the Staff would not be permitted to grant additional time for the Company to regain compliance with respect to that deficiency, nor would the Company be afforded an applicable cure or compliance period. Instead, the Staff would issue a “Delist Determination Letter” and the Company would have an opportunity to request a Nasdaq hearing panel regarding its continued listing. The Company continues to seek additional capital through strategic transactions and from other financing alternatives. Without additional capital, current working capital and cash generated from sales will not provide adequate funding to make debt repayments, for research, sales and marketing efforts and product development activities at their current levels. If sufficient capital is not raised, the Company will at a minimum need to significantly reduce or curtail its research and development and other operations, and this would negatively affect its ability to achieve corporate growth goals. Should the Company fail to raise additional cash from outside sources, this would have a material adverse impact on its operations. The accompanying financial statements have been prepared assuming the Company will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to its ability to continue as a going concern.

Line of Credit Facility	9 Months Ended	12 Months Ended
Line of Credit Facility	Sep. 30, 2025	Dec. 31, 2024
Line of Credit Facility [Abstract]
Line of Credit Facility	10. Line of Credit Facility On May 31, 2024, the Company drew down $3.3 million on a margin loan facility under a line of credit (the “Pershing Credit Facility”) with Pershing LLC (“Pershing”), an affiliate of The Bank of New York Mellon Corporation. The available credit line limit under the Pershing Credit Facility fluctuated based on the Company’s request for extensions from time to time, subject to the value of the collateralized marketable securities the Company holds with Pershing, provided that the amount available to draw under the Pershing Credit Facility cannot exceed 91.5% of the value of the collateralized marketable securities deposited with Pershing. Depending on the value of the marketable securities the Company held with Pershing, Pershing could have required the Company from time-to-time to deposit additional funds or marketable securities in order to restore the level of collateral to an acceptable level. The amounts borrowed under the Pershing Credit Facility were due on demand. As of September 30, 2025 and December 31, 2024, the Company held collateralized marketable securities with Pershing with a total value of zero and $3.5 million, respectively. Borrowings under the Pershing Credit Facility bore interest at the target interest rate set by the Federal Open Market Committee, subject to a floor of 5.5%, plus a spread of 1.75% and applicable fees of 0.5%, subject to a maximum interest rate of the then applicable Prime Rate as published in The Wall Street Journal, plus 3.0%. Interest payments thereunder were calculated on a monthly basis and, unless paid, were added to the outstanding balance under the Pershing Credit Facility. The proceeds under the Pershing Credit Facility are available for working capital needs and other general corporate purposes. Volatility in the global markets could cause the interest rate to fluctuate from time to time increasing the Company’s costs, or could cause Pershing to terminate the Company’s ability to borrow funds. In addition, borrowings under the Pershing Credit Facility have the effect of limiting the Company’s use of cash and marketable securities. On January 3, 2025, the Pershing Credit Facility was fully repaid and the collateralized marketable securities were fully redeemed.	10. Line of Credit Facility On May 31, 2024, the Company drew down $3.3 million on a new margin loan facility under a line of credit (the “Pershing Credit Facility”) with Pershing LLC (“Pershing”), an affiliate of The Bank of New York Mellon Corporation. The available credit line limit under the Pershing Credit Facility fluctuated based on the Company’s request for extensions from time to time, subject to the value of the collateralized marketable securities the Company holds with Pershing, provided that the amount available to draw under the Pershing Credit Facility cannot exceed 91.5% of the value of the collateralized marketable securities deposited with Pershing. Depending on the value of the marketable securities the Company held with Pershing, Pershing could have required the Company from time-to-time to deposit additional funds or marketable securities in order to restore the level of collateral to an acceptable level. The amounts borrowed under the Pershing Credit Facility were due on demand. As of December 31, 2024, the Company held collateralized marketable securities with Pershing with a total value of $3.5 million. Borrowings under the Pershing Credit Facility bore interest at the target interest rate set by the Federal Open Market Committee, subject to a floor of 5.5%, plus a spread of 1.75% and applicable fees of 0.5%, subject to a maximum interest rate of the then applicable Prime Rate as published in The Wall Street Journal plus 3.0%. Interest payments thereunder were calculated on a monthly basis and, unless paid, were added to the outstanding balance under the Pershing Credit Facility. The proceeds under the Pershing Credit Facility are available for working capital needs and other general corporate purposes. Volatility in the global markets could cause the interest rate to fluctuate from time to time increasing the Company’s costs, or could cause Pershing to terminate the Company’s ability to borrow funds. In addition, borrowings under the Pershing Credit Facility have the effect of limiting the Company’s use of cash and marketable securities. On January 3, 2025, the Pershing Credit Facility was fully repaid and the collateralized marketable securities were fully redeemed.

Commitments and Contingencies - Summary of Future Minimum Annual Lease Payments under Operating Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
2025		$ 69
2026		11
Total minimum lease payments		80
Less: amount representing interest		5
Present value of obligations under leases		75
Less: current portion	$ 21	44	$ 120
Noncurrent operating lease liability		$ 31	$ 85

Short-Term Investments (Tables)

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

Summary of Contractual Maturities of Available-for-sale Securities

The following table summarizes contractual maturities of

available-for-sale

securities as of September 30, 2025 (in thousands):


	Amortized Cost		Estimated Fair Value
Due in one year or less	$	2,309	$	2,309
Due after one year through five years		—		—
Due after five years		1,003		1,003

Total Investments	$	3,312	$	3,312

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Composition of Certain Financial Statement Captions (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Composition Of Certain Financial Statement Captions [Abstract]

Other Current Assets

As of September 30, 2025 and December 31, 2024, other current assets were comprised of the following (in thousands):


	September 30, 2025		December 31, 2024
Prepaid services	$	551	$	87
Deferred costs (Note 8)		299		436
Prepaid insurance		135		559

Total other current assets	$	985	$	1,082

Other Current Assets

As of December 31, 2024 and 2023, other current assets were comprised of the following (in thousands):


	December 31,
	2024		2023
Prepaid services	$	87	$	410
Deferred costs (Note 7)		436		234
Prepaid insurance		559		636

	$	1,082	$	1,280

Property and Equipment, Net

Property and Equipment, net

As of December 31, 2024 and 2023, property and equipment, net, were comprised of the following (in thousands):


	December 31,
	2024			2023
Office and computer equipment	$	1,778		$	1,632
Leasehold improvements		1,810			1,810

		3,588			3,442
Less accumulated depreciation		(3,140	)		(2,536	)

	$	448		$	906

Intangible Assets, Net

As of December 31, 2024 intangible assets, net, were comprised of the following (in thousands):


	December 31, 2024
	Gross Carrying Amount		Accumulated Amortization			Intangible Asset, Net
Software	$	221	$	(218	)	$	3
Intellectual Property		546		(80	)		466

Total intangible assets	$	767	$	(298	)	$	469

As of December 31, 2023 intangible assets, net, were comprised of the following (in thousands):


	December 31, 2023
	Gross Carrying Amount		Accumulated Amortization			Intangible Asset, Net
Software	$	221	$	(179	)	$	42

Total intangible assets	$	221	$	(179	)	$	42

Future Amortization Expense on Intangible Assets

As of December 31, 2024, future amortization expense on intangible assets is estimated to be as follows (in thousands):


Year Ending December 31,	Amount
2025		140
2026		136
2027		136
2028		57

Total future amortization expense	$	469

Accounts Payable and Accrued Expenses

As of December 31, 2024 and 2023, accounts payable and accrued expenses were comprised of the following (in thousands):


	December 31,
	2024		2023
Accounts payable	$	9,474	$	4,758
Accrued payroll and bonus		920		987
Accrued professional fees		236		128
Accrued vacation and compensation		356		370
Accrued R&D studies		185		388
Accrued interest		117		—

	$11,288		$6,631

Subsequent Events - Additional Information (Details)											1 Months Ended			3 Months Ended	12 Months Ended
Subsequent Events - Additional Information (Details)	Oct. 28, 2025 $ / shares	Oct. 16, 2025 USD ($) ft²	Jun. 17, 2025 $ / shares shares	May 02, 2025 shares	Mar. 07, 2025 USD ($)	Mar. 04, 2025 USD ($) $ / shares shares	Feb. 13, 2025 USD ($) $ / shares shares	May 09, 2024 shares	May 08, 2024 USD ($) shares	May 05, 2024 shares	Oct. 29, 2025 USD ($) shares	Oct. 27, 2025 USD ($) shares	Mar. 31, 2025 $ / shares	Jun. 30, 2024 shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Sep. 30, 2025 USD ($) $ / shares	May 19, 2025 $ / shares
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) \| $ / shares															$ 0.001	$ 0.001	$ 0.001
Liability in accounts payable and accrued expenses \| $															$ 11,288,000	$ 6,631,000	$ 11,623,000
Additional paid-in capital \| $															485,024,000	479,274,000	515,574,000
Monthly base rent \| $															$ 180,000	$ 141,000
Series A Warrant [Member]
Subsequent Event [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares																		$ 0.4373
Common Stock [Member]
Subsequent Event [Line Items]
Issue and sale of share														1,439,988	1,439,988	2,230,493
Common Stock [Member] \| Series B Warrant [Member]
Subsequent Event [Line Items]
Number of shares sold				21,482,492
February 2025 SPEA Agreements
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) \| $ / shares							$ 0.001
Warrant exercise price (in dollars per share) \| $ / shares							1.12
Purchase price of share \| $ / shares							$ 0.125
Maturity date							Feb. 13, 2026
Interest Rate							10.00%
Aggregate purchase price \| $							$ 3,700,000
Proceeds from private placement \| $							4,200,000
February 2025 SPEA Agreements \| SPEA Warrants [Member]
Subsequent Event [Line Items]
Aggregate purchase price \| $							4,200,000
February 2025 SPEA Agreements \| Common Stock [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $							$ 3,300,000
Number of securities called by warrant or right							3,002,009
May 2024 Purchase Agreement
Subsequent Event [Line Items]
Aggregate principal amount \| $							$ 3,200,000		$ 3,188,922
May 2024 Purchase Agreement \| Common Stock [Member] \| Series A Warrant [Member]
Subsequent Event [Line Items]
Number of shares sold									3,591,532
March 2025 Private Placement [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $							$ 3,400,000
Liability in accounts payable and accrued expenses \| $																	$ 6,400,000
Percentage agreed to repay purchasers holding securities			115.00%
March 2025 Private Placement [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $						$ 3,200,000
March 2025 Private Placement [Member] \| Private Placement Share [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares			$ 0.66
March 2025 Private Placement [Member] \| Prefunded Warrant [Member]
Subsequent Event [Line Items]
Number of securities called by warrant or right			10,633,650
Purchase price of share \| $ / shares			$ 0.659
March 2025 Private Placement [Member] \| Series A Warrant [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						22,727,270
March 2025 Private Placement [Member] \| Series A Warrant [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						5,314,870
March 2025 Private Placement [Member] \| Series A Warrant [Member] \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of shares sold						28,042,138
March 2025 Private Placement [Member] \| Series B Warrant [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						22,727,270
March 2025 Private Placement [Member] \| Series B Warrant [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						5,314,870
March 2025 Private Placement [Member] \| Series B Warrant [Member] \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of shares sold						28,042,138
March 2025 Private Placement [Member] \| Common Stock [Member]
Subsequent Event [Line Items]
Proceeds from private placement \| $					$ 15,000,000
Maximum beneficial ownership percentage						4.99%
Maximum beneficial ownership percentage by election of holder						9.99%
March 2025 Private Placement [Member] \| Common Stock [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						3,077,270
March 2025 Private Placement [Member] \| Common Stock [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						992,468
March 2025 Private Placement [Member] \| Common Stock [Member] \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of shares sold						4,069,738
Warrant exercise price (in dollars per share) \| $ / shares						$ 0.001
Issue and sale of share						28,042,140
March 2025 Private Placement [Member] \| Common Stock [Member] \| Private Placement Share [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares						$ 0.66
March 2025 Private Placement [Member] \| Common Stock [Member] \| Prefunded Warrant [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares						0.659
March 2025 Private Placement [Member] \| Common Stock [Member] \| Series A Warrant [Member]
Subsequent Event [Line Items]
Number of shares sold								3,591,532		3,591,532
Warrant exercise price (in dollars per share) \| $ / shares						$ 1.32
Expiration period						5 years
March 2025 Private Placement [Member] \| Common Stock [Member] \| Series B Warrant [Member]
Subsequent Event [Line Items]
Number of shares sold								3,591,532		3,591,532
Warrant exercise price (in dollars per share) \| $ / shares						$ 1.98
Expiration period						2 years 6 months
Subsequent Event [Member]
Subsequent Event [Line Items]
Liability declined \| $												$ 1,300,000
Reduction of liability settled in cash with increase to stockholders equity \| $												900,000
Payment in connection with private placement \| $												$ 400,000
Shares returned and cancelled												600,000
Subsequent Event [Member] \| Amendment Agreement [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares	$ 0.66
No longer required percentage of proceeds to repay purchasers from capital raised	90.00%
Percentage agreed to repay purchasers holding securities	115.00%
Subsequent Event [Member] \| LG 1 Property Owner LP
Subsequent Event [Line Items]
Area of space \| ft²		11,370
Lessee, operating lease, lease not yet commenced, description		The Houston Lease is expected to commence on or about November 1, 2026
Monthly base rent \| $		$ 58,745
Lease initial term		120 months
Lease annual increase rate of base rent		3.00%
Subsequent Event [Member] \| Lincoln Park Capital Fund, LLC [Member]
Subsequent Event [Line Items]
Additional paid-in capital \| $											$ 1,900,000
Subsequent Event [Member] \| February 2025 SPEA Agreements
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) \| $ / shares							$ 0.001
Warrant exercise price (in dollars per share) \| $ / shares							1.12
Purchase price of share \| $ / shares							$ 0.125
Maturity date							Feb. 13, 2026
Interest Rate							10.00%
Aggregate purchase price \| $							$ 3,700,000
Reduction of exercise price of Warrants \| $ / shares													$ 0.125
Subsequent Event [Member] \| February 2025 SPEA Agreements \| SPEA Warrants [Member]
Subsequent Event [Line Items]
Number of securities called by warrant or right							3,002,009
Aggregate purchase price \| $							$ 4,250,000
Subsequent Event [Member] \| February 2025 SPEA Agreements \| Common Stock [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $							$ 3,362,251
Number of securities called by warrant or right							3,002,009
Subsequent Event [Member] \| March 2025 Private Placement [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $							$ 3,362,251
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Aggregate principal amount \| $						$ 3,200,000
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Series A Warrant [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						22,727,270
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Series A Warrant [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						5,314,870
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Series B Warrant [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						22,727,270
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Series B Warrant [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						5,314,870
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member]
Subsequent Event [Line Items]
Proceeds from private placement \| $					$ 15,000,000
Maximum beneficial ownership percentage						4.99%
Maximum beneficial ownership percentage by election of holder						9.99%
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| New Capital Subscriptions [Member]
Subsequent Event [Line Items]
Number of shares sold						22,727,270
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Exchange [Member]
Subsequent Event [Line Items]
Number of shares sold						5,314,870
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares						$ 0.001
Issue and sale of share						28,042,140
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Private Placement Share [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares						$ 0.66
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Prefunded Warrant [Member]
Subsequent Event [Line Items]
Purchase price of share \| $ / shares						0.659
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Series A Warrant [Member]
Subsequent Event [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares						$ 1.32
Expiration period						5 years
Subsequent Event [Member] \| March 2025 Private Placement [Member] \| Common Stock [Member] \| Series B Warrant [Member]
Subsequent Event [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares						$ 1.98
Expiration period						2 years 6 months
Subsequent Event [Member] \| Lincoln Park Purchase Credit Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member]
Subsequent Event [Line Items]
Number of shares sold											3,300,000

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Revenue	$ 1,397	$ 1,456	$ 3,846	$ 4,412	$ 5,824	$ 4,913
Revenue, Product and Service [Extensible Enumeration]	Grant [Member]	Grant [Member]	Grant [Member]	Grant [Member]	Grant [Member]	Grant [Member]
Operating expenses:
Research and development	$ 2,436	$ 2,858	$ 5,438	$ 8,394	$ 10,580	$ 9,690
General and administrative	3,443	2,397	7,964	6,813	9,939	8,544
Total operating expenses	5,879	5,255	13,402	15,207	20,519	18,234
Operating loss	(4,482)	(3,799)	(9,556)	(10,795)	(14,695)	(13,321)
Other income (expense):
Interest income	59	80	87	219	273	400
Interest expense		(61)	(548)	(122)	(179)	(395)
Financing expense					(3,545)
Financing expenses			(3,061)	(3,545)
Warrant issuance costs		(54)	(964)	(486)	(486)
Change in fair value of warrants			(800)		5,654
Change in fair value of derivative instruments		960	(2,631)	5,654
Total other income (expense)	59	925	(7,117)	1,720	1,717	5
Net loss	$ (4,423)	$ (2,874)	$ (16,673)	$ (9,075)	$ (12,978)	$ (13,316)
Net loss per share of common stock - basic	$ (0.04)	$ (0.37)	$ (0.29)	$ (1.46)	$ (1.95)	$ (4.24)
Net loss per share of common stock - diluted	$ (0.04)	$ (0.37)	$ (0.29)	$ (1.67)	$ (2.34)	$ (4.24)
Weighted average number of shares of common stock outstanding - basic	107,428,969	7,855,763	57,845,406	6,232,123	6,640,251	3,140,925
Weighted average number of shares of common stock outstanding - diluted	107,428,969	7,855,763	57,845,406	8,452,338	7,700,774	3,140,925

Line of Credit Facility - Additional Information (Details) - Pershing Credit Facility [Member] - USD ($) $ in Millions	May 31, 2024	Sep. 30, 2025	Dec. 31, 2024
Line of Credit Facility [Line Items]
Line of credit	$ 3.3
Percentage of credit facility cannot exceed collateralized marketable securities	91.50%
Collateralized marketable securities		$ 0.0	$ 3.5
Debt instrument floor rate	5.50%
Basis variable rate	1.75%
Applicable fees	0.50%
Maximum interest rate	3.00%

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References + Details

Offsets	Jan. 09, 2026 USD ($) shares
Offset: 1
Offset Payment:
Offset Claimed	true
Rule 457(p) Offset	true
Registrant or Filer Name	Plus Therapeutics, Inc.
Form or Filing Type	S-3
File Number	333-286393
Initial Filing Date	Apr. 04, 2025
Fee Offset Claimed	$ 3,970.38
Security Type Associated with Fee Offset Claimed	Equity
Security Title Associated with Fee Offset Claimed	Common Stock, par value $0.001 per share
Unsold Securities Associated with Fee Offset Claimed \| shares	0
Unsold Aggregate Offering Amount Associated with Fee Offset Claimed	$ 0.00
Offset Note	A filing fee of $194,082.78 was previously paid in connection with the registration statement on Form S-3 (No. 333-286393) filed by the registrant on April 4, 2025 (the "Prior Registration Statement"). The registrant withdrew the Prior Registration Statement by filing a Form RW on June 23, 2025. As the Prior Registration Statement was not declared effective, no securities were sold thereunder. Accordingly, the full $194,082.78 filing fee previously paid in connection with the Prior Registration Statement remains available to be used to offset the fee currently due and additional fees that may become due for future registration statements. In accordance with Rule 457(p) of the Securities Act, such previously paid filing fee will offset the filing fee of $3,970.38 currently due pursuant to this registration statement.
Termination / Withdrawal Statement	The Prior Registration Statement (as defined below) was not declared effective and no securities were sold thereunder.
Offset: 2
Offset Payment:
Offset Claimed	false
Rule 457(p) Offset	true
Registrant or Filer Name	Plus Therapeutics, Inc.
Form or Filing Type	S-3
File Number	333-286393
Filing Date	Apr. 04, 2025
Fee Paid with Fee Offset Source	$ 194,082.78

Fees Summary	Jan. 09, 2026 USD ($)
Fees Summary [Line Items]
Total Offering	$ 28,750,000.00
Previously Paid Amount	0.00
Total Fee Amount	3,970.38
Total Offset Amount	3,970.38
Net Fee	$ 0.00

CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY/(DEFICIT) (UNAUDITED) - USD ($)	Total	Lincoln Park Purchase Agreement	Convertible Preferred Stock [Member]	Preferred Stock [Member]	Preferred Stock [Member] Series F Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member] Lincoln Park Purchase Agreement	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Lincoln Park Purchase Agreement	Accumulated Deficit [Member]
Balance at Dec. 31, 2022	$ 6,445,000					$ 2,000			$ 473,628,000		$ (467,185,000)
Balance (in shares) at Dec. 31, 2022			1,952			2,240,092
Stock-based compensation	569,000								569,000
Purchase of treasury stock	(126,000)							$ (126,000)
Purchase of treasury stock (in Shares)								(78,559)
Net loss	(13,316,000)										(13,316,000)
Issuance of common stock	5,005,000					$ 3,000			5,002,000
Issuance of common stock (in shares)					1	2,230,493
Redemption of Series F preferred stock (in shares)				(1)
Issuance of common stock for in process research and development	75,000								75,000
Issuance of common stock for in process research and development (in shares)						53,381
Fractional adjustment						(1,310)
Balance at Dec. 31, 2023	$ (1,348,000)					$ 5,000		$ (126,000)	479,274,000		(480,501,000)
Balance (in shares) at Dec. 31, 2023			1,952			4,522,656
Balance, Treasury (in shares) at Dec. 31, 2023	78,559							(78,559)
Stock-based compensation	$ 146,000								146,000
Purchase of treasury stock	(374,000)							$ (374,000)
Purchase of treasury stock (in Shares)								(179,866)
Net loss	(3,261,000)										(3,261,000)
Balance at Mar. 31, 2024	(4,837,000)					$ 5,000		$ (500,000)	479,420,000		(483,762,000)
Balance (in shares) at Mar. 31, 2024			1,952			4,522,656
Balance, Treasury (in shares) at Mar. 31, 2024								(258,425)
Balance at Dec. 31, 2023	$ (1,348,000)					$ 5,000		$ (126,000)	479,274,000		(480,501,000)
Balance (in shares) at Dec. 31, 2023			1,952			4,522,656
Balance, Treasury (in shares) at Dec. 31, 2023	78,559							(78,559)
Net loss	$ (9,075,000)
Balance at Sep. 30, 2024	(5,174,000)					$ 6,000		$ (500,000)	484,896,000		(489,576,000)
Balance (in shares) at Sep. 30, 2024			1,952			6,154,758
Balance, Treasury (in shares) at Sep. 30, 2024								(258,425)
Balance at Dec. 31, 2023	$ (1,348,000)					$ 5,000		$ (126,000)	479,274,000		(480,501,000)
Balance (in shares) at Dec. 31, 2023			1,952			4,522,656
Balance, Treasury (in shares) at Dec. 31, 2023	78,559							(78,559)
Stock-based compensation	$ 550,000								550,000
Purchase of treasury stock	(374,000)							$ (374,000)
Purchase of treasury stock (in Shares)								(179,866)
Net loss	(12,978,000)										(12,978,000)
Issuance of common stock	1,000					$ 1,000
Issuance of common stock (in shares)						1,439,988
Exercise of pre-funded warrants (in Shares)						192,114
Reclassification of warrants to equity	5,200,000								5,200,000
Balance at Dec. 31, 2024	$ (8,949,000)					$ 6,000		$ (500,000)	485,024,000		(493,479,000)
Balance (in shares) at Dec. 31, 2024			1,952			6,154,758
Balance, Treasury (in shares) at Dec. 31, 2024	258,425							(258,425)
Balance at Mar. 31, 2024	$ (4,837,000)					$ 5,000		$ (500,000)	479,420,000		(483,762,000)
Balance (in shares) at Mar. 31, 2024			1,952			4,522,656
Balance, Treasury (in shares) at Mar. 31, 2024								(258,425)
Stock-based compensation	151,000								151,000
Net loss	(2,940,000)										(2,940,000)
Issuance of common stock	1,000					$ 1,000
Issuance of common stock (in shares)						1,439,988
Balance at Jun. 30, 2024	(7,625,000)					$ 6,000		$ (500,000)	479,571,000		(486,702,000)
Balance (in shares) at Jun. 30, 2024			1,952			5,962,644
Balance, Treasury (in shares) at Jun. 30, 2024								(258,425)
Stock-based compensation	125,000								125,000
Net loss	(2,874,000)										(2,874,000)
Exercise of pre-funded warrants (in Shares)						192,114
Reclassification of warrants to equity	5,200,000								5,200,000
Balance at Sep. 30, 2024	(5,174,000)					$ 6,000		$ (500,000)	484,896,000		(489,576,000)
Balance (in shares) at Sep. 30, 2024			1,952			6,154,758
Balance, Treasury (in shares) at Sep. 30, 2024								(258,425)
Balance at Dec. 31, 2024	$ (8,949,000)					$ 6,000		$ (500,000)	485,024,000		(493,479,000)
Balance (in shares) at Dec. 31, 2024			1,952			6,154,758
Balance, Treasury (in shares) at Dec. 31, 2024	258,425							(258,425)
Stock-based compensation	$ 148,000								148,000
Net loss	(17,401,000)										(17,401,000)
Exercise of pre-funded warrants						$ 7,000			(7,000)
Exercise of pre-funded warrants (in Shares)						6,535,731
Exercise of Series B Warrants from May 2024 PIPE	882,000								882,000
Exercise of Series B Warrants from May 2024 PIPE (in shares)						497,824
Exchange of warrants for notes payable	(3,694,000)								(3,694,000)
Issuance of common stock, pre-funded warrants and warrants for debt repayment	5,373,000					$ 4,000			5,369,000
Issuance of common stock, pre-funded warrants and warrants for debt repayment (in shares)						4,069,738
Balance at Mar. 31, 2025	(23,641,000)					$ 17,000		$ (500,000)	487,722,000		(510,880,000)
Balance (in shares) at Mar. 31, 2025			1,952			17,258,051
Balance, Treasury (in shares) at Mar. 31, 2025								(258,425)
Balance at Dec. 31, 2024	$ (8,949,000)					$ 6,000		$ (500,000)	485,024,000		(493,479,000)
Balance (in shares) at Dec. 31, 2024			1,952			6,154,758
Balance, Treasury (in shares) at Dec. 31, 2024	258,425							(258,425)
Net loss	$ (16,673,000)
Balance at Sep. 30, 2025	$ 5,054,000					$ 132,000		$ (500,000)	515,574,000		(510,152,000)
Balance (in shares) at Sep. 30, 2025			1,952			131,863,969
Balance, Treasury (in shares) at Sep. 30, 2025	258,425							(258,425)
Balance at Mar. 31, 2025	$ (23,641,000)					$ 17,000		$ (500,000)	487,722,000		(510,880,000)
Balance (in shares) at Mar. 31, 2025			1,952			17,258,051
Balance, Treasury (in shares) at Mar. 31, 2025								(258,425)
Stock-based compensation	152,000								152,000
Net loss	5,151,000										5,151,000
Issuance of common stock		$ 2,746,000					$ 10,000			$ 2,736,000
Issuance of common stock (in shares)							10,187,000
Exercise of pre-funded warrants						$ 9,000			(9,000)
Exercise of pre-funded warrants (in Shares)						9,016,349
Reclassification of warrants to equity	10,967,000								10,967,000
Exercise or exchange of March 2025 Series A and B Warrants	858,000					$ 56,000			802,000
Exercise or exchange of March 2025 Series A and B Warrants (in Shares)						56,277,032
Cancellation of common stock (in Shares)						(300,000)
Modification of warrants (Note 13)	6,801,000								6,801,000
Balance at Jun. 30, 2025	3,034,000					$ 92,000		$ (500,000)	509,171,000		(505,729,000)
Balance (in shares) at Jun. 30, 2025			1,952			92,438,432
Balance, Treasury (in shares) at Jun. 30, 2025								(258,425)
Stock-based compensation	527,000								527,000
Net loss	(4,423,000)										(4,423,000)
Issuance of common stock		$ 16,850,000					$ 35,000			$ 16,815,000
Issuance of common stock (in shares)							34,388,496
Exercise of pre-funded warrants						$ 8,000			(8,000)
Exercise of pre-funded warrants (in Shares)						7,767,941
Cancelled common stock						$ (3,000)			3,000
Cancellation of common stock (in Shares)						(3,472,740)
Investor fees pursuant to Support Letters (Note 13)	(2,250,000)								(2,250,000)
Exercise of March 2025 Series B Warrants (in Shares)						741,840
Liability to investors pursuant to Letter Agreement (Note 13)	(8,684,000)								(8,684,000)
Balance at Sep. 30, 2025	$ 5,054,000					$ 132,000		$ (500,000)	$ 515,574,000		$ (510,152,000)
Balance (in shares) at Sep. 30, 2025			1,952			131,863,969
Balance, Treasury (in shares) at Sep. 30, 2025	258,425							(258,425)

Income Taxes

12 Months Ended

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Income Taxes

13. Income Taxes

Pursuant to the Internal Revenue Code (“IRC”) of 1986, as amended, specifically IRC §382 (“Section 382”) and IRC §383, the Company’s ability to use net operating loss (“NOLs”) and R&D tax credit carry forwards (“tax attribute carry forwards”) to offset future taxable income is limited if the Company experiences a cumulative change in ownership of more than 50% within a three-year testing period. The Company’s use of federal and state NOLs and research credits could be limited further by the provisions of Section 382 depending upon the timing and amount of additional equity securities that the Company has issued or will issue. State NOL carryforwards may be similarly limited. If a change in ownership were to have occurred, NOL and tax credits carryforwards could be eliminated or restricted. If eliminated, the related asset would be removed from the deferred tax asset schedule with a corresponding reduction in the valuation allowance. Due to the existence of the valuation allowance, limitations created by ownership changes, if any, will not impact the Company’s effective tax rate.

The Company has recorded a full valuation allowance against its net deferred tax assets and due to our net losses for the years ended December 31, 2024 and 2023, there was no provision or benefit for income taxes recorded.

The table below summarizes the Company’s net loss before income tax provision for the years ended December 31, 2024 and 2023 (in thousands):


	2024			2023
Domestic	$	(12,978	)	$	(13,316	)
Foreign		—			—
Net loss before provision for income taxes	$	(12,978	)	$	(13,316	)

A reconciliation of the total income tax provision tax rate to the statutory federal income tax rates of 21.0% for the years ended December 31, 2024 and 2023, respectively, is as follows:


	2024			2023
Income tax expense (benefit) at federal statutory rate		(21.0	)%		(21.0	)%
Change in valuation allowance		23.8	%		25.5	%
Income tax benefit at state statutory rate		(0.3	)%		(0.2	)%
Share-based compensation		0.9	%		1.0	%
Warrants		(2.6	)%		—
NOLs expiring and adjustments to NOL		(0.1	)%		(0.1	)%
Research credit		(0.7	)%		(5.1	)%
Return to provision		—			(0.1	)%

		(0.0	)%		0.0	%

The tax effects of temporary differences that give rise to significant portions of our deferred tax assets and deferred tax liabilities as of December 31, 2024 and 2023 are as follows (in thousands):


	2024		2023
Deferred tax assets:
Accrued expenses	$	249	$	269
Share-based compensation		94		99
Net operating loss carryforwards		15,412		13,397
Income tax credit carryforwards		1,725		1,630
Property and equipment, net		218		154
Intangible assets		730		685
Capitalized R&D		3,949		2,842


	2024			2023
Other, net		213			453
Total deferred tax assets		22,590			19,529
Valuation allowance		(22,575	)		(19,486	)

Total deferred tax assets, net of allowance		15			43

Deferred tax liabilities:
Other		(15	)		(43	)

Total deferred tax liability		(15	)		(43	)

Net deferred tax assets (liability)	$	—		$	—

The Company has established a valuation allowance against its net deferred tax assets due to the uncertainty surrounding the realization of such assets. The Company periodically evaluates the recoverability of the deferred tax assets. At such time as it is determined that it is more likely than not that deferred tax assets are realizable, the valuation allowance will be reduced. The Company has recorded a full valuation allowance of $22.6 million as of December 31, 2024 as it does not believe it is more likely than not the net deferred tax assets will be realized. The Company increased its valuation allowance by approximately $3.1 million during the year ended December 31, 2024.

At December 31, 2024, the Company had federal and state tax loss carry forwards of approximately $72.6 million, and $3.3 million, respectively. The federal and state net operating loss carry forwards begin to expire in 2037 and 2044, if unused, respectively. The federal net operating loss carryover includes $69.2 million of net operating losses generated after 2017. Federal net operating losses generated from 2018 onwards carryover indefinitely and may generally be used to offset up to 80% of future taxable income. At December 31, 2024, the Company had federal tax credit carry forwards of approximately $1.9 million, before reduction for uncertain tax positions. The federal credits will begin to expire in 2039, if unused. In addition, at December 31, 2024, the Company had state tax credit carry forwards of approximately $0.2 million, before reduction for uncertain tax positions. The state credits will begin to expire in 2039, if unused.

The Company follows the provisions of income tax guidance which provides recognition criteria and a related measurement model for uncertain tax positions taken or expected to be taken in income tax returns. The guidance requires that a position taken or expected to be taken in a tax return be recognized in the financial statements when it is more likely than not that the position would be sustained upon examination by tax authorities. Tax positions that meet the more likely than not threshold are then measured using a probability weighted approach recognizing the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement. The Company has not recognized any liability for uncertain tax positions as of December 31, 2024 and 2023.

Following is a tabular reconciliation of the unrecognized tax benefits activity during the years ended December 31, 2024 and 2023 (in thousands):


	2024			2023
Unrecognized Tax Benefits – Beginning	$	408		$	209
Gross decreases – tax positions in prior period		(5	)		(16	)
Gross increase – current-period tax positions		21			215

Unrecognized Tax Benefits – Ending	$	424		$	408

The unrecognized tax benefit amounts are reflected in the determination of the Company’s deferred tax assets. If recognized, none of these amounts would affect the Company’s effective tax rate, since it would be offset by an equal reduction in the deferred tax asset valuation allowance. The Company does not foresee material changes to its liability for uncertain tax benefits within the next twelve months.

The Company did not recognize interest related to unrecognized tax benefits in interest expense and penalties in operating expenses for the year ended December 31, 2024.

The Company files income tax returns with the United States and various state jurisdictions. The Company is currently not under examination by the Internal Revenue Service or any other taxing authority.

With few exceptions, the Company’s tax years prior to 2021 are no longer open to examination by the taxing authority. While not open to examination, the tax attributes generated in tax years prior to 2021 remain subject to adjustment by the taxing authorities if utilized in tax years which are still open to examination.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147477617/942-740-50-1

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-Topic 235
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-Topic 740
-SubTopic 10
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
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-Topic 946
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-Topic 235
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-Subparagraph (SX 210.4-08(h)(2))
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-Subparagraph (b)
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-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

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-Topic 740
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-Section S99
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-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Impairment related to long lived assets or goodwill	$ 0	$ 0

Composition of Certain Financial Statement Captions - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Property and Equipment, net [Abstract]
Office and computer equipment		$ 1,778	$ 1,632
Leasehold improvements		1,810	1,810
Property and equipment, gross		3,588	3,442
Less accumulated depreciation		(3,140)	(2,536)
Property and equipment, net	$ 273	$ 448	$ 906

Stock-Based Compensation (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock Option Activity

A summary of stock option activity for the nine months ended September 30, 2025 is as follows:


	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2024		598,540		$	7.08		9.00	$	—
Granted		10,800,137		$	0.61		—	$	—
Cancelled/forfeited/expired		(125,814	)	$	4.50		—	$	—

Outstanding as of September 30, 2025		11,272,863		$	0.91		9.76	$	1,103

Vested and expected to vest at September 30, 2025		10,073,271		$	0.94		9.75	$	980
Exercisable at September 30, 2025		692,781		$	5.15		8.99	$	33

A summary of activity for the year ended December 31, 2024 is as follows:


	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Balance as of December 31, 2023		140,109		$	37.48		8.07
Granted		506,127			1.58
Cancelled/forfeited		(47,696	)		38.02

Balance as of December 31, 2024		598,540		$	7.08		9.00	$	—

Vested and expected to vest at December 31, 2024		547,893		$	7.52		9.00	$	—

Exercisable at December 31, 2024		144,739		$	22.96		7.60	$	—

Weighted-average Assumptions

The fair value of each option awarded during the years ended December 31, 2024 and 2023 was estimated on the date of grant using the Black-Scholes-Merton option valuation model based on the following weighted-average assumptions:


	December 31, 2024			December 31, 2023
Expected term		6.0 years			6.0 years
Risk-free interest rate		3.79	%		4.06	%
Expected volatility		120.6	%		127.0	%
Dividends		0	%		0	%
Resulting fair value	$	1.39		$	4.47

Summary of Share-Based Compensation Recognized

The following table summarizes share-based compensation recognized during the years ended December 31, 2024 and 2023 in the statement of operations (in thousands):


	Years ended December 31,
	2024		2023
Research and development	$	51	$	66
General and administrative		499		503

Total share-based compensation	$	550	$	569

Summary of Restricted Stock Unit Activity

A summary of restricted stock unit activity for the nine months ended September 30, 2025 is as follows:


	Shares		Weighted Average Grant Date Fair Value
Unvested as of December 31, 2024		—	$	—
Granted		2,823,857	$	0.57
Vested		—	$	—
Cancelled/forfeited		—	$	—

Unvested as of September 30, 2025		2,823,857	$	0.57

Investments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Sep. 30, 2025	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Total investments	$ 3,500		$ 0
Debt Securities, available-for-sale, amortized cost and fair value	$ 3,500	$ 3,312
Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-sales and short-term investments date of purchase term	1 year

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Section 50
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Income Taxes - Summary of Company's Net Loss Before Income Tax Provision (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Income Taxes [Line Items]
Net income loss	$ (4,423)	$ 5,151	$ (17,401)	$ (2,874)	$ (2,940)	$ (3,261)	$ (16,673)	$ (9,075)	$ (12,978)	$ (13,316)
Domestic [Member]
Income Taxes [Line Items]
Net income loss									(12,978)	(13,316)
Foreign [Member]
Income Taxes [Line Items]
Net income loss									$ 0	$ 0

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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+ Details

Stockholders' Equity

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Stockholders Equity Note [Abstract]

Stockholders' Equity

13. Stockholders’ Equity

Preferred Stock

The Company has authorized 5,000,000 shares of preferred stock, par value $0.001 per share. The Company’s board of directors is authorized to designate the terms and conditions of any preferred stock the Company issues without further action by the common stockholders.

Series B and C Preferred Stock

As of September 30, 2025, there were 938 outstanding shares of Series C Preferred Stock that can be converted into an aggregate of 27,792 shares of common stock, and 1,014 shares of Series B Convertible Preferred Stock that can be converted into an aggregate of 398 shares of common stock.

Common Stock

February 2025 SPEA Agreements

On February 13, 2025 (the “February 2025 Closing Date”), the Company entered into a Securities Purchase and Exchange Agreement (the “February 2025 SPEA”) with certain existing accredited investors (the “February 2025 Purchasers”). Pursuant to the February 2025 SPEA, on the February 2025 Closing Date the Company issued secured convertible promissory notes (the “Funding Notes”) in the aggregate principal

amount

of $

3.3

million together with common stock purchase warrants (the “February 2025 Warrants”) to purchase

3,002,009

shares of the Company common stock, par value $

0.001

and exercise price of $

1.12

per share (the “February 2025 Warrant Exercise Price”). The aggregate purchase price for the Funding Notes and the February 2025 Warrants was approximately $

3.7

million (the “Aggregate Purchase Price”) and included proceeds from the February 2025 Purchasers of $

0.125

per February 2025 Warrant in accordance with Nasdaq listing rules. The Funding Notes would mature on February 13, 2026, and bore interest at a rate of

% per annum, subject to increase upon events of default. The February 2025 Warrants were exercisable for five-years from the date of issuance.

The Funding Notes, accrued interest and February 2025 warrants were repurchased by the Company subsequent to consummation of the March 2025 Private Placement for proceeds of $4.2 million.

Security Interest

The obligations of the Company under the February 2025 SPEA, Funding Notes and Exchange Notes (as defined below) were secured by a pledge of substantially all of the assets of the Company pursuant to a security agreement, dated as of the February 2025 Closing Date, among the Company, CNSide Diagnostics, LLC (a subsidiary of the Company, “CNSide Diagnostics”), and Iroquois Master Fund Ltd., as collateral agent for the February 2025 Purchasers (the “Security Agreement”), subject to certain exceptions. The Security Agreement contained certain customary affirmative and negative covenants, including limitations on the Company’s and CNSide Diagnostic’s ability to dispose of assets, subject to customary exceptions. The repayment of the Company’s obligations under the February 2025 SPEA and Notes were guaranteed pursuant to a subsidiary guarantee, dated as of the February 2025 Closing Date (the “Subsidiary Guarantee”), by and among CNSide Diagnostics and the February 2025 Purchasers. The Security Agreement and the Subsidiary Guarantee were subsequently terminated after the closing of the private placement pursuant to the March 2025 SPA (as defined below).

Exchange Notes

As disclosed below, the Company entered into the May 2024 Purchase Agreement (defined below), with the May 2024 Purchasers for the private placement of securities, including the May 2024 Series A Warrants to purchase an aggregate of up to 3,591,532 shares of common stock. The May 2024 Purchase Agreement included certain limitations and restrictions on the Company’s ability to issue securities and provided the May 2024 Purchasers and the other investors signatories to the May 2024 Purchase Agreement participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “Financing Restrictions”). On the February 2025 Closing Date, pursuant to the February 2025 SPEA, the Company issued to the May 2024 Purchasers secured convertible promissory notes in the aggregate amount of $3.2 million (the “Exchange Notes”) in exchange for cancellation of the May 2024 Series A Warrants held by the May 2024 Purchasers, and the May 2024 Purchasers entered into a second amendment to the May 2024 Purchase Agreement to eliminate the Financing Restrictions. The terms and conditions of the Exchange Notes were substantially identical in all material respects to the Funding Notes. The Security Agreement and Subsidiary Guarantee also applied to the obligations under the Exchange Notes. The Exchange Notes were exchanged after the closing of the March 2025 Private Placement as defined below.

Both the Funding Notes and the Exchange Notes contained embedded conversion features that were required to be bifurcated and accounted for as derivative liabilities. The Company evaluated authoritative guidance for accounting for convertible debt instruments and elected to account for the Funding Notes and Exchange Notes at fair value. Consequently, the Company recorded the Funding Notes and Exchange Notes in their entirety at fair value at issuance and immediately before settlement, with changes in fair value recorded as change in fair value of derivative instruments in the condensed consolidated statements of operations between the issuance date and the settlement date.

The Company entered into the transaction due to immediate funding requirements. Under authoritative guidance, if the fair value of a warrant liability exceeds the proceeds received in an arm’s length transaction

with no rights

or privileges that require separate accounting recognition as an asset identified, then the warrant liability is recorded at fair value with the excess of fair value over proceeds recognized as a loss in earnings. The Exchange Notes, Funding Notes and associated warrants were recorded at fair value on the issuance date at $3.8 million, $4.0 million and $2.7 million, respectively. The excess of the fair value of the instruments issued over cash received of $3.7 million and the carrying value of the May 2024 Series A Warrants exchanged of $3.7 million, in the amount of $3.1 million was recorded as a financing expense in the statement of operations for the nine months ended September 30, 2025.

Changes in the fair value of Exchange Notes, Funding Notes and February 2025 Warrants between issuance date and settlement date, in the amount of a gain of $0.3 million, a gain of $0.3 million and a gain of $2.2 million, respectively, were recorded as change in the fair value of derivative instruments in the statement of operations for the nine months ended September 30, 2025.

March 2025 Private Placement

On March 4, 2025, the Company entered into a securities purchase agreement (the “March 2025 SPA”) with accredited investors, including certain existing stockholders of the Company (collectively, the “March 2025 Private Placement Purchasers”) for a private placement of securities (the “March 2025 Private Placement”). The March 2025 SPA, provided for the sale and issuance by the Company of an aggregate of

28,042,140

shares (the “March 2025 Private Placement Shares”) of the Company’s common stock, or, at the election of each March 2025 Private Placement Purchaser,

pre-funded

warrants to purchase Common Stock (the “March 2025

Pre-Funded

Warrants”), exercisable immediately at an exercise price of $0.001 per share (the “March 2025

Pre-Funded

Warrant Shares”), with each March 2025 Private Placement Share or March 2025

Pre-Funded

Warrant accompanied by (i) a Series A common warrant (the “March 2025 Series A Warrants”) to purchase one share of common stock (the “March 2025 Series A Warrant Shares”), and (ii) one Series B common warrant (the “March 2025 Series B Warrants”) to purchase one share of common stock (see below for additional details on the Series B Warrants cashless exercise provisions) (the “March 2025 Series B Warrant Shares,” and together with the March 2025 Series A Warrant Shares, the “March 2025 Common Warrant Shares”). The March 2025 Private Placement Shares, March 2025

Pre-Funded

Warrants, March 2025

Pre-Funded

Warrant Shares, March 2025 Series A Warrants, March 2025 Series B Warrants, and the March 2025 Common Warrant Shares are collectively referred to herein as the “March 2025 Securities.” Pursuant to the March 2025 SPA, the Company issued to the March 2025 Private Placement Purchasers

4,069,738

March 2025 Private Placement Shares,

23,972,400

March 2025

Pre-Funded

Warrants,

28,042,138

March 2025 Series A Warrants and

28,042,138

March 2025 Series B Warrants. As of September 30, 2025, all March 2025 Series A Warrants and March 2025 Series B Warrants were settled as a result of cancellation, exchanges or exercises as detailed below, and

2,611,809

March 2025

Pre-Funded

Warrants remained outstanding.

The combined purchase price of $0.66 for each March 2025 Private Placement Share or $0.659 for each March 2025

Pre-Funded

Warrant in the March 2025 Private Placement, together with one accompanying March 2025 Series A Warrant and one accompanying March 2025 Series B Warrant, represents the applicable “Minimum Price” in accordance with Nasdaq Rule 5635(d).

The initial exercise price of each March 2025 Series A Warrant issued in the March 2025 Private Placement was $1.32 per share of common stock. The March 2025 Series A Warrants were exercisable only following stockholder approval and expire five (5) years thereafter. The March 2025 Series A Warrants were subject to certain price reset, share combination event and anti-dilution provisions which, if triggered, provided that the number of shares issuable upon exercise of the March 2025 Series A Warrants would downward adjust, subject to a floor price of $0.132 (the “Floor Price”), and the number of shares issuable upon exercise therefor would increase such that the aggregate exercise price remained unchanged. The March 2025 Series A Warrants were extinguished as part of the Letter Agreement on June 17, 2025 as discussed below.

The initial exercise price of each March 2025 Series B Warrant issued in the March 2025 Private Placement was $1.98 per share of common stock. The March 2025 Series B Warrants were exercisable only following

stockholder approval

and expire two and

one-half

(2.5)

years thereafter. The March 2025 Series B Warrants were subject to certain price reset and share combination event provisions which, if triggered, provided that the number of shares issuable upon exercise of the March 2025 Series B Warrants would downward adjust, subject to the Floor Price, and the number of shares issuable upon exercise therefor would increase such that the aggregate exercise price remained unchanged. In addition, the March 2025 Series B Warrant alternative cashless exercise provision provided that the March 2025 Series B Warrant could be exercised without further payment to the Company and for three times the number of shares of common stock then subject to the March 2025 Series B Warrant.

The March 2025

Pre-Funded

Warrants will be exercisable from the date of issuance until exercised in full. The March 2025

Pre-Funded

Warrants, March 2025 Series A Warrants and March 2025 Series B Warrants may not be exercised to the extent that immediately following such exercise, the holder would beneficially own greater than 4.99% (or, at the election of the holder, greater than 9.99%) of the Company’s outstanding common stock.

In connection with the March 2025 Private Placement, the Company issued 3,077,270 shares of common stock, 19,650,000 shares of March 2025

Pre-Funded

Warrants in lieu thereof, and accompanying 22,727,270 March 2025 Series A Warrants and 22,727,270 March 2025 Series B Warrants in consideration of new capital subscriptions. In addition, the Company issued 992,468 shares of common stock, 4,322,400 March 2025

Pre-Funded

Warrants in lieu thereof, and accompanying 5,314,870 March 2025 Series A Warrants and 5,314,870 March 2025 Series B Warrants, were issued in exchange for the cancelation of approximately $3.2 million in aggregate principal amount of the Exchange Notes.

The Company evaluated the terms of the February 2025 Warrants, March 2025 Series A Warrants and March 2025 Series B Warrants under authoritative guidance and concluded that each of the instruments should be accounted for as a liability instrument at fair value at issuance and each subsequent balance sheet date until settlement, with changes in the fair value recorded in the condensed consolidated statement of operations. The March 2025

Pre-Funded

Warrants meet the criteria to be recorded as equity in the Company’s condensed consolidated balance sheet.

The March 2025 Private Placement closed on March 7, 2025 (the “March 2025 Closing Date”). The aggregate gross proceeds at the March 2025 Closing Date totaled approximately $15.0 million. The gross proceeds, along with the fair value of the February 2025 Warrants of $0.5 million and Exchange Notes of $3.5 million as of the settlement date of March 4, 2025, were first allocated to the warrant liability instruments at their full fair value, totaling $13.2 million, with the remainder of $5.8 million recorded to common stock and additional

paid-in

capital in equity of the condensed consolidated balance sheet. Total offering expenses of $1.4 million were allocated based on the allocated amount of proceeds to warrant liabilities and equity, with $1.0 million recorded as warrant issuance expenses and expensed as incurred, and the remaining $0.4 million recorded as common stock issuance costs in additional

paid-in

capital.

On May 2, 2025, the Company’s stockholders approved, among other things, the March 2025 Series A Warrants and March 2025 Series B Warrants, and an amendment to the Company’s Certificate of Incorporation, as amended, to increase the authorized share capital of the Company to an amount sufficient to cover the shares of common stock issuable upon the exercise of the March 2025 Series A Warrants and March 2025 Series B Warrants. As part of the March 2025 Series A Warrants and March 2025 Series B Warrants agreement, the exercise price of the March 2025 Series A Warrants and March 2025 Series B Warrants were both reset on May 19, 2025 to $0.4373 per share. Prior to modification of the March 2025 Series B Warrants as part of the Letter Agreement (as further described below), certain March 2025 Series B Warrants were cashless exercised for the issuance of 21,482,492 shares of common stock The liability classified March 2025 Series B Warrants were remeasured immediately prior to exercise, which resulted in a $3.8 million gain on change in fair value for the nine months ended September 30, 2025, and a $0.8 million credit to additional

paid-in

capital.

Letter Agreement

On June 17, 2025, the Company and the March 2025 Private Placement Purchasers entered into a letter agreement (the “Letter Agreement”) with each of the March 2025 Private Placement Purchasers in an effort to, among other items, minimize the dilutive impact of the March 2025 Private Placement. The Letter Agreement extinguished the March 2025 Series A Warrants, modified the March 2025 Series B Warrants, and provided for the return and cancellation of Private Placement Shares and

Pre-Funded

Warrants, as further discussed in the following paragraphs.

As part of the Letter Agreement, all March 2025 Series A Warrants were cancelled. As of March 31, 2025, the fair value of the March 2025 Series A Warrant liability was $5.0 million. On June 17, 2025, the March 2025 Series A Warrants were immediately remeasured to fair value prior to their cancellation, which resulted in a $2.7 million gain on change in fair value attributable to the March 2025 Series A Warrants for the nine months ended September 30, 2025. The extinguishment of the March 2025 Series A Warrants was recognized as a $2.3 million capital contribution and recorded to additional

paid-in

capital, as the extinguishment was deemed equivalent to a capital contribution by existing shareholders of the Company.

As part of the same transaction, the March 2025 Series B Warrants were amended (the “Amended March 2025 Series B Warrants”), to (a) reduce the overall number of March 2025 Series B Warrant Shares issuable upon exercise of the Series B Warrants to an aggregate of up to 35,536,380 Series B Warrant Shares, (b) reduce the alternative cashless exercise ratio in such March 2025 Series B Warrants from 3:1 to 1:1, (c) remove provisions contained in the March 2025 Series B Warrants that would otherwise reduce the Company’s stockholders’ equity, and (d) reset the exercise price of the Amended March 2025 Series B Warrants back to $1.98 per share. As a result of the Letter Agreement, the Amended March 2025 Series B Warrants no longer fail the indexation guidance under ASC 815, Derivatives and Hedging, resulting in a reclassification from liability to equity. Immediately prior to reclassification, the March 2025 Series B Warrant liability was remeasured, and $4.5 million was recognized as a capital contribution and recorded to additional

paid-in

capital, as the modification of the March 2025 Series B Warrants was deemed equivalent to a capital contribution by existing shareholders of the Company. The remeasured fair value of the March 2025 Series B warrant liability, in the amount of $11.0 million was reclassified to equity. After the June 17, 2025 modification, 34,794,540 of the Amended March 2025 Series B Warrants were cashless exercised resulting in the issuance of 34,794,540 shares of common stock.

Lastly, in conjunction with the Letter Agreement, each of the March 2025 Private Placement Purchasers agreed to return an aggregate of 12,241,986 Private Placement Shares and

Pre-Funded

Warrants issuable for an aggregate of 10,633,650

Pre-Funded

Warrant Shares, held by them as of the date of the Letter Agreement, upon request of the Company (the “Letter Agreement Repurchase Option”), which were issued pursuant to the March 2025 Private Placement Purchase Agreement for a value of $0.66 per Private Placement Share and $0.659 per

Pre-Funded

Warrant. In exchange therefor, the Company agreed to repay the March 2025 Private Placement Purchasers holding such securities 115% of such value, using 90% of the proceeds from any capital raised by the Company subsequent to July 1, 2025. The Company and each of the March 2025 Private Placement Purchasers also agreed to waive any restrictions on subsequent equity sales and variable rate transactions contained in March 2025 Private Placement Purchase Agreement to allow for such repayment. During the three and nine months ended September 30, 2025, the Company paid the March 2025 Private Placement Purchasers $2.3 million and 3,472,740 shares were returned and cancelled under the terms of the Letter Agreement.

Support Letters

On July 11, 2025, the Company and certain March 2025 Private Placement Purchasers party to the Letter Agreement entered into that certain letter of support (the “Support Letters”) to modify certain portions of the Letter Agreement as between the Company and each of such March 2025 Private Placement Purchasers. In the event that the Company reasonably believes that, within the 30 days (the “Modification Period”) prior to the end of any fiscal quarter, the Company will have stockholders’ equity in an amount below $3.0 million

as of the

end of such fiscal quarter (the “Potential Equity Deficiency”), the Subsequent Financing Percentage (as defined in the Letter Agreement) shall be modified from

% to

% for any Subsequent Financing (as defined in the Letter Agreement) that occurs during the Modification Period pursuant to the Lincoln Park Purchase Agreement. Upon the end of the Modification Period, the Subsequent Financing Percentage shall be reverted to

%, and such percentage shall apply to all Subsequent Financings, including all Subsequent Financings pursuant to the Lincoln Park Purchase Agreement. In the event the Company desires to trigger the modification of the Subsequent Financing Percentage, the Company agrees to supply the purchaser who executed a Support Letter with a pro forma balance sheet to evidence its reasonable belief of the Potential Equity Deficiency approximately

days prior to each end of fiscal quarter once the books for prior months are closed. In accordance with the Support Letters, the Company made a cash payment of $

0.5

million to such purchasers for a total cash payment of $

2.3

million, which was recorded as a reduction to additional

paid-in

capital in the condensed consolidated balance sheet as of September

2025

. Such payment counted as cash received by the purchaser towards its Maximum Amount. Each Support Letter also granted the purchaser party to the letter a participation right in certain future financings of the Company for a period of

months.

First Amendment to the February 2025 SPEA

In connection with entering into the March 2025 SPA, the Company entered into that certain First Amendment to the February 2025 SPEA (the “First Amendment”). The February 2025 SPEA included certain limitations and restrictions on the Company’s ability to issue securities and provided the investors with participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “New Financing Restrictions”). Pursuant to the First Amendment, subject to consummation of the March 2025 Private Placement, the Company agreed to repurchase from the Investors $3.4 million in principal amount of the Company’s Funding Notes and accrued interest, along with the February 2025 Warrants issued pursuant to the February 2025 SPEA for an aggregate purchase price of $4.2 million. In exchange for the repurchase by the Company of the Funding Notes and SPEA Warrants, the February 2025 Purchasers agreed to consent to the March 2025 Private Placement and eliminate the New Financing Restrictions.

May 2024 Private Placement

On May 5, 2024, the Company entered into a securities purchase agreement (the “May 2024 Securities Purchase Agreement”) with certain investors, including certain of the Company’s directors and executive officers (“Company Insiders”) (collectively, the “May 2024 Purchasers”), for the sale and issuance by the Company of its securities (the “Initial Subscription”). On May 8, 2024, the Company entered into a first amendment to the May 2024 Securities Purchase Agreement (together with the May 2024 Securities Purchase Agreement, the “May 2024 Purchase Agreement”), for the sale and issuance by the Company of additional securities to two of the May 2024 Purchasers (the “Additional Subscription,” and together with the Initial Subscription, the “May 2024 Private Placement”). The May 2024 Purchase Agreement provides for the sale and issuance by the Company of an aggregate of 3,591,532 shares (the “May 2024 Private Placement Shares”) of the Company’s common stock or, at the election of each May 2024 Purchaser,

Pre-Funded

warrants (the “May 2024

Pre-Funded

Warrants”), exercisable immediately at an exercise price of $0.001 per share, with each May 2024 Private Placement Share or May 2024

Pre-Funded

Warrant accompanied by (i) a May 2024 Series A common warrant (“May 2024 Series A Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 May 2024 Series A Warrants, and (ii) one May 2024 Series B common warrant (“May 2024 Series B Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 May 2024 Series B Warrants.

The combined purchase price for each May 2024 Private Placement Share and May 2024

Pre-Funded

Warrant from the Initial Subscription was $2.022, and $2.158 from the Additional Subscription, in each case together with one accompanying May 2024 Series A Warrant and one accompanying May 2024 Series B Warrant provided, that the Company Insiders participated in the Initial Subscription at an offering price of

$2.04 per May 2024 Private Placement Share and accompanying May 2024 Series A Warrant and May 2024 Series B Warrant.

The exercise price of May 2024 Series A Warrants and May 2024 Series B Warrants from the Initial Subscription is $1.772 per share from the Initial Subscription and $1.908 per share from the Additional Subscription, provided that the exercise price for the May 2024 Series A Warrants and May 2024 Series B Warrants issued to the Company Insiders is $1.79 per share. Subject to certain ownership limitations, the May 2024 Series A Warrants will be exercisable until May 9, 2029, which is the five-year anniversary of issuance. Subject to certain ownership limitations, the May 2024 Series B Warrants will be exercisable until May 9, 2029. The May 2024

Pre-Funded

Warrant will not expire until exercised in full.

Prior to the Amendment and Restatements (as defined below), if a holder of a May 2024 Series A Warrant or a May 2024 Series B Warrant was unable to exercise the warrant due to the limitation contained in the warrant that restricts the holder from owning above a specified beneficial ownership level (generally 4.99% or 9.99%) as the result of exercise of the warrant, then the holder had the right to elect upon exercise of the warrant to receive a May 2024

Pre-Funded

Warrant for the same number of shares of common stock that would otherwise have been received upon exercise of the warrant. In addition, prior to the Amendment and Restatements, the May 2024 Series A Warrants and May 2024 Series B Warrants provided for a call right starting June 24, 2025, in favor of the Company, if the volume-weighted average price of the shares of common stock exceeds specified prices.

The May 2024 Private Offering closed on May 9, 2024. The Company issued 1,439,988 shares of common stock, 2,151,544 May 2024

Pre-Funded

Warrants, 3,591,532 May 2024 Series A Warrants and 3,591,532 May 2024 Series B Warrants to purchase shares of its common stock in connection with the May 2024 Private Placement. The net proceeds from the May 2024 Private Placement were approximately $7.3 million.

The Company reviewed the terms of the May 2024

Pre-Funded

Warrants, May 2024 Series A Warrants and May 2024 Series B Warrants under the authoritative accounting guidance as of the issuance date.

As described above, the May 2024 Series A Warrants and May 2024 Series B Warrants were initially classified as liabilities for the reason that they could have been exercised into either shares of common stock or May 2024

Pre-Funded

Warrants at the holder’s option and thus failed the indexation guidance under ASC 815, Derivatives and Hedging. The May 2024 Series A Warrant and May 2024 Series B Warrant liability were initially recorded at fair value as of the issuance date, and under the terms of the May 2024 Series A Warrants and May 2024 Series B Warrants when issued that liability was subject to adjustment to estimated fair value at each balance sheet date until the warrants were settled. Refer below for additional information regarding the amendment of the May 2024 Series A Warrants and May 2024 Series B Warrants that eliminated the ability of the May 2024 Series A Warrants and May 2024 Series B Warrants to be exercised into

Pre-Funded

Warrants, and as a result, the reclassification of the May 2024 Series A and B Warrants from liability to equity section of the consolidated balance sheet.

The May 2024

Pre-Funded

Warrants are equity classified because they (1) are freestanding financial instruments that are legally detachable and separately exercisable from the common stock, (2) are immediately exercisable, (3) do not embody an obligation for the Company to repurchase its shares, (4) permit the holder to receive a fixed number of shares of common stock upon exercise, (5) are indexed to the Company’s common stock and (6) meet the equity classification criteria.

The proceeds from the May 2024 Private Placement were first allocated to the full fair value of the May 2024 Series A Warrants and May 2024 Series B Warrants due to the initial liability classification. As disclosed in Note 4, Fair Value Measurements, the fair value of the May 2024 Series A Warrants and May 2024 Series B Warrants at issuance was $10.9 million. Under authoritative guidance, if the fair value of a warrant liability exceeds the proceeds received in an arm’s length transaction with no rights or privileges that require separate accounting recognition as an asset identified, then the warrant liability is recorded at fair value with the excess of fair value over proceeds recognized as a loss in earnings. The Company

recognized

approximately $

3.5

million in financing expense in the consolidated statement of operations during year ended December

2024

, which represents the excess of the fair value of the

May 2024

Series A Warrants and

May 2024

Series B Warrants at issuance over the proceeds. During the year ended December

2024

, the Company recognized a fair value gain on warrant liability of $

5.7

million. Proceeds from the

May 2024

Private Placement are shown as cash from financing transactions and the gain on warrant liability is included as an adjustment to reconcile the net loss to net cash used in operating activities in the consolidated statements of cash flows for the year ended December

2024

In addition, total offering expenses related to the May 2024 Private Placement of $0.4 million were recorded as a component of other expenses as the entire proceeds were allocated to the warrant liability, which, prior to the amendment described below, could be settled with either the Company’s shares of common stock or May 2024

Pre-Funded

Warrants, which are exercisable into the Company’s shares of common stock at any time at the holders’ option, but not in cash payment to the holders.

Amendment and Restatement of May 2024 Series A Warrants and May 2024 Series B Warrants

On August 9, 2024, the Company amended and restated the May 2024 Series A Warrants and May 2024 Series B Warrants (the “Amendment and Restatements”) issued in the May 2024 Private Placement. The Amendment and Restatements eliminated the ability of the holders of the May 2024 Series A Warrants and May 2024 Series B Warrants to elect to purchase

Pre-Funded

Warrants upon exercise of the May 2024 Series A Warrants and May 2024 Series B Warrants in lieu of shares of common stock if the holder would have been restricted because of the specified beneficial ownership level in the May 2024 Series A Warrants and May 2024 Series B Warrants.

In addition, the Amendment and Restatements eliminated the Company’s call right under the terms of the May 2024 Series A Warrants to call the May 2024 Series A Warrants after June 24, 2025, if the volume-weighted average price of shares of common stock exceeded specified prices. There were no other changes in the terms of the May 2024 Series A Warrants and May 2024 Series B Warrants.

As a result of the Amendment and Restatements, the May 2024 Series A Warrants and May 2024 Series B Warrants, as amended, no longer fail the indexation guidance under ASC 815, Derivatives and Hedging, and the fair value of the warrant liability at the amendment date, in the amount of $5.2 million, was reclassified to equity.

Lincoln Park Purchase Agreement

On June 17, 2025, the Company entered into a purchase agreement (the “Lincoln Park Purchase Agreement”) and a registration rights agreement (the “Registration Rights Agreement”) with Lincoln Park Capital Fund, LLC (“Lincoln Park”), pursuant to which the Company has the right, but not the obligation, to sell to Lincoln Park, and Lincoln Park committed to purchase up to $50.0 million of shares of the Company’s common stock, $0.001 par value per share. Such sales of common stock by the Company are subject to certain limitations and conditions set forth in the Lincoln Park Purchase Agreement including, but not limited to, the filing and effectiveness of a registration statement (a “Lincoln Park Registration Statement”). As of September 30, 2025, under the Lincoln Park Registration Statements, the resale of up to a total of 50,000,000 shares are reserved for issuance and sale under the Lincoln Park Purchase Agreement.

Under the Lincoln Park Purchase Agreement, on any business day selected by the Company over the

36-month

period commencing on June 23, 2025 (the “Purchase Date”), the Company may direct Lincoln Park to purchase up to 300,000 shares of common stock on such Purchase Date, so long as the closing stock price on The Nasdaq Capital Market is not below $0.10 on the applicable Purchase Date (a “Regular Purchase”); provided, however, that (i) a Regular Purchase may be increased to up to 400,000 shares, if the closing sale price per share of the common stock on The Nasdaq Capital Market is not below $0.50 on the applicable Purchase Date; and (ii) a Regular Purchase may be increased to up to 500,000 shares, if the closing sale price per share of the common stock on The Nasdaq Capital Market is not below $0.75 on the applicable Purchase Date. In any case, Lincoln Park’s maximum obligation under any single Regular

Purchase

will not exceed $1.0 million. The above-referenced share amount limitations and closing sale price thresholds are subject to adjustment for any reorganization, recapitalization,

non-cash

dividend, stock split, reverse stock split or other similar transaction as provided in the Purchase Agreement. The purchase price per share for each such Regular Purchase will be 97% of the lesser of: (i) the lowest sale price for the common stock on The Nasdaq Capital Market on the date of sale, and (ii) the average of the three lowest closing sale prices for the common stock on The Nasdaq Capital Market during the 10 consecutive business days ending on the business day immediately preceding the purchase date.

The Company also has the right to direct Lincoln Park, on any business day on which the Company has properly submitted a Regular Purchase notice for the maximum amount the Company is then permitted to sell to Lincoln Park in such Regular Purchase, to purchase an additional amount of the common stock (an “Accelerated Purchase”) of additional shares based on criteria established in the Lincoln Park Purchase Agreement. The purchase price per share for each such Accelerated Purchase will be 96.5% of the lesser of: (i) the volume weighted average price (“VWAP”) during a specific time window on the Accelerated Purchase date as defined in the Lincoln Park Purchase Agreement, and (ii) the closing sale price of the Company’s common stock on The Nasdaq Capital Market on the same Accelerated Purchase date.

In addition to the Regular Purchase and Accelerated Purchase, the Company can sell to Lincoln Park an additional amount of common stock (an “Additional Accelerated Purchases”), which can be initiated multiple times on the same Additional Accelerated Purchase date. The purchase price per share for each such Additional Accelerated Purchase will be 96.5% of the lesser of: (i) the VWAP during a specific time windows on the Additional Accelerated Purchase date as defined in the Lincoln Park Purchase Agreement, and (ii) the closing sale price of the Company’s common stock on The Nasdaq Capital Market on the same Additional Accelerated Purchase date.

The sales of shares of common stock to Lincoln Park through a Regular Purchase, an Accelerated Purchase and an Additional Accelerated Purchases, depend upon a variety of factors to be determined by the Company from time to time, including, among others, market conditions, the trading price of the common stock and determinations by the Company as to the appropriate sources of funding for the Company and its operations. The net proceeds under the Lincoln Park Purchase Agreement to the Company depend on the frequency and prices at which the Company sells shares of its stock to Lincoln Park.

In accordance with the Lincoln Park Purchase Agreement, the Company was required to pay Lincoln Park an initial commitment fee of $0.5 million, which was paid through the issuance of 1,612,903 shares of common stock on August 14, 2025. The initial commitment fee was recorded as a reduction to additional

paid-in

capital in the condensed consolidated balance sheet as of September 30, 2025. The Company has agreed to pay an additional commitment fee of $0.5 million, which it may elect to pay in cash or shares of its common stock, or a combination of cash and shares of its common stock, upon receipt of $25.0 million aggregate gross proceeds from sales of common stock to Lincoln Park under the Lincoln Park Purchase Agreement.

As of the nine months ended September 30, 2025, the Company issued 44,575,496 shares under the Lincoln Park Purchase Agreement for gross proceeds of approximately $19.6 million. The Company incurred approximately $50,000 for legal fees in connection with the Lincoln Park Purchase Agreement.

Outstanding Warrants

As of September 30, 2025, the Company had the following warrants outstanding:


	September 30, 2025
May 2024 Series A Warrants		48,285
May 2024 Series B Warrants		3,093,708
March 2025 Pre-Funded Warrants		2,611,809

Total		5,753,802

One share of common stock is issuable for each warrant up

on e

xercise.

15. Stockholders’ Equity

Preferred Stock

The Company has authorized 5,000,000 shares of preferred stock, par value $0.001 per share. The Board is authorized to designate the terms and conditions of any preferred stock the Company issues without further action by the common stockholders.

Series F Preferred Stock

On March 3, 2023, the Company filed a certificate of designation (the “Certificate of Designation”) with the Secretary of State of the State of Delaware, effective as of the time of filing, designating the rights, preferences, privileges and restrictions of the Series F Preferred Stock, with the total authorization of one (1) share of Series F Preferred Stock. The Certificate of Designation provided that the share of Series F Preferred Stock would have 50,000,000 votes per share of Series F Preferred Stock and would vote together with the Company’s common stock as a single class exclusively with respect to any proposal to amend the Company’s certificate of incorporation to effect a reverse stock split. On March 3, 2023, the Company entered into a subscription and investment representation agreement with Richard J. Hawkins, chairman of the board of the Company, who is an accredited investor (the “Series F Preferred Stock Purchaser”), pursuant to which the Company agreed to issue and sell one (1) share of the Company’s Series F Preferred Stock, par value $0.001 per share, to the Series F Preferred Stock Purchaser for $1,000 in cash. The sale closed on March 3, 2023.

The outstanding share of Series F Preferred Stock was redeemed in whole, automatically effective upon the approval by the Company’s stockholders of the reverse stock split in April 2023. Upon such redemption, the Series F Preferred Stock Purchaser received consideration of $1,000 in cash.

On November 12, 2024, the Company filed a Certificate of Elimination (“Certificate of Elimination”) with the Secretary of State of the State of Delaware effecting the elimination of the Certificate of Designation relating to the Series F Preferred Stock. Following the filing of the Certificate of Elimination the previously authorized share of the Series F Preferred Stock resumed the status of an undesignated share of the Company’s preferred stock.

Series B and C Preferred Stock

As of December 31, 2024, there were 938 outstanding shares of Series C Preferred Stock that can be converted into an aggregate of 27,792 shares of common stock, and 1,014 shares of Series B Convertible Preferred Stock that can be converted into an aggregate of 398 shares of common stock.

Common Stock

May 2024 Private Placement

On May 5, 2024, the Company entered into a securities purchase agreement (the “Securities Purchase Agreement”) with certain investors, including certain of the Company’s directors and executive officers (“Company Insiders”) (collectively, the “Purchasers”), for the sale and issuance by the Company of its securities (the “Initial Subscription”). On May 8, 2024, the Company entered into a first amendment to the Securities Purchase Agreement (together with the Securities Purchase Agreement, the “Purchase Agreement”), for the sale and issuance by the Company of additional securities to two of the Purchasers (the “Additional Subscription,” and together with the Initial Subscription, the “May 2024 Private Placement”). The Purchase Agreement provides for the sale and issuance by the Company of an aggregate of 3,591,532 shares (the “Private Placement Shares”) of the Company’s common stock or, at the election of each Purchaser,

pre-funded

warrants (the

“Pre-Funded

Warrants”), exercisable immediately at an exercise price of $0.001 per share, with each Private Placement Share or

Pre-Funded

Warrant accompanied by (i) a Series A common warrant (“Series A Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 Series A Warrants, and (ii) one Series B common warrant (“Series B Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 Series B Warrants.

The combined purchase price for each Private Placement Share and

Pre-Funded

Warrant from the Initial Subscription was $2.022, and $2.158 from the Additional Subscription, in each case together with one accompanying Series A Warrant and one accompanying Series B Warrant provided, that the Company Insiders participated in the Initial Subscription at an offering price of $2.04 per Private Placement Share and accompanying Series A Warrant and Series B Warrant.

The exercise price of Series A Warrants and Series B Warrants from the Initial Subscription is $1.772 per share from the Initial Subscription and $1.908 per share from the Additional Subscription, provided that the exercise price for the Series A Warrants and Series B Warrants issued to the Company Insiders is $1.79 per share. Subject to certain ownership limitations, the Series A Warrants will be exercisable until May 9, 2029, which is the five-year anniversary of issuance. Subject to certain ownership limitations, the Series B Warrants will be exercisable until June 24, 2025. The

Pre-Funded

Warrant will not expire until exercised in full.

Prior to the Amendment and Restatements (as defined below), if a holder of a Series A Warrant or a Series B Warrant was unable to exercise the warrant due to the limitation contained in the warrant that restricts the holder from owning above a specified beneficial ownership level (generally 4.99% or 9.99%) as the result of exercise of the warrant, then the holder had the right to elect upon exercise of the warrant to receive a

Pre-Funded

Warrant for the same number of shares of common stock that would otherwise have been received upon exercise of the warrant. In addition, prior to the Amendment and Restatements, the Series A Warrants and Series B Warrants provided for a call right starting June 24, 2025, in favor of the Company, if the volume-weighted average price of the shares of common stock exceeds specified prices.

The May 2024 Private Offering closed on May 9, 2024. The Company issued 1,439,988 shares of common stock, 2,151,544

Pre-Funded

Warrants, 3,591,532 Series A Warrants and 3,591,532 Series B Warrants to purchase shares of its common stock in connection with the May 2024 Private Placement. The net proceeds from the May 2024 Private Placement were approximately $7.3 million.

The Company reviewed the terms of the

Pre-Funded

Warrants, Series A Warrants and Series B Warrants under the authoritative accounting guidance as of the issuance date.

As described above, the Series A Warrants and Series B Warrants were initially classified as liabilities for the reason that they could have been exercised into either shares of common stock or

Pre-Funded

Warrants at the holder’s option and thus failed the indexation guidance under ASC 815, Derivatives and Hedging. The Series A Warrant and Series B Warrant liability were initially recorded at fair value as of the issuance date, and under the terms of the Series A Warrants and Series B Warrants when issued that liability was subject to adjustment to estimated fair value at each balance sheet date until the warrants were settled. Refer below for

additional information regarding the amendment of the Series A Warrants and Series B Warrants that eliminated the ability of the Series A Warrants and Series B Warrants to be exercised into

Pre-Funded

Warrants, and as a result, the reclassification of the Series A and B Warrants from liability to equity section of the consolidated balance sheet.

The

Pre-Funded

The proceeds from the May 2024 Private Placement were first allocated to the full fair value of the Series A Warrants and Series B Warrants due to the initial liability classification. As disclosed in Note 3, Fair Value Measurements, the fair value of the Series A Warrants and Series B Warrants at issuance was $10.9 million. Under authoritative guidance, if the fair value of a warrant liability exceeds the proceeds received in an arm’s length transaction with no rights or privileges that require separate accounting recognition as an asset identified, then the warrant liability is recorded at fair value with the excess of fair value over proceeds recognized as a loss in earnings. The Company recognized approximately $3.5 million in financing expense in the consolidated statement of operations during year ended December 31, 2024, which represents the excess of the fair value of the Series A Warrants and Series B Warrants at issuance over the proceeds. During the year ended December 31, 2024, the Company recognized a fair value gain on warrant liability of $5.7 million. Proceeds from the May 2024 Private Placement are shown as cash from financing transactions and the gain on warrant liability is included as an adjustment to reconcile the net loss to net cash used in operating activities in the statements of cash flows for the year ended December 31, 2024.

Pre-Funded

Warrants, which are exercisable into the Company’s shares of common stock at any time at the holders’ option, but not in cash payment to the holders.

As of December 31, 2024, all of the Series A Warrants, and Series B Warrants issued in connection with the May 2024 Private Placement remained outstanding, and

Pre-Funded

Warrants to purchase 1,959,430 shares of the Company’s common stock remained outstanding.

Amendment and Restatement of Series A Warrants and Series B Warrants

On August 9, 2024, the Company amended and restated the Series A Warrants and Series B Warrants (the “Amendment and Restatements”) issued in the May 2024 Private Placement. The Amendment and Restatements eliminated the ability of the holders of the Series A Warrants and Series B Warrants to elect to purchase

Pre-Funded

Warrants upon exercise of the Series A Warrants and Series B Warrants in lieu of shares of common stock if the holder would have been restricted because of the specified beneficial ownership level in the Series A Warrants and Series B Warrants.

In addition, the Amendment and Restatements eliminated the Company’s call right under the terms of the Series A Warrants to call the Series A Warrants after June 24, 2025, if the volume-weighted average price of shares of common stock exceeded specified prices. There were no other changes in the terms of the Series A Warrants and Series B Warrants.

As a result of the Amendment and Restatements, the Series A Warrants and Series B Warrants, as amended, no longer fail the indexation guidance under ASC 815, Derivatives and Hedging, and the fair value of the warrant liability at the amendment date, in the amount of $5.2 million, was reclassified to equity.

Lincoln Park Purchase Agreement

On August 2, 2022, the Company entered into a purchase agreement (the “2022 Purchase Agreement”) and registration rights agreement pursuant to which Lincoln Park Capital Fund (“Lincoln Park”) committed to purchase up to $50.0 million of the Company’s common stock. Under the terms and subject to the conditions of the 2022 Purchase Agreement, the Company has the right, but not the obligation, to sell to Lincoln Park, and Lincoln Park is obligated to purchase up to $50.0 million of the Company’s common stock. Such sales of common stock by the Company are subject to certain limitations, and can occur from time to time, at the Company’s sole discretion, over the

36-month

period commencing on August 17, 2022, subject to the satisfaction of certain conditions.

On May 16, 2022, the Company received stockholder approval for purposes of the Nasdaq listing rules to permit issuances of up to 57.5 million shares of the Company’s common stock (including the issuance of more than 19.99% of the Company’s common stock) to Lincoln Park, and it was pursuant to that approval that the Company entered into the 2022 Purchase Agreement.

Upon execution of the 2022 Purchase Agreement, the Company paid $0.1 million in cash as the initial commitment fee, and issued 32,846 shares as the initial commitment shares, to Lincoln Park as consideration for its irrevocable commitment to purchase shares of the Company’s common stock at its direction under the 2022 Purchase Agreement. The Company has agreed to pay an additional commitment fee, which it may elect to pay in cash or shares of its common stock, or a combination of cash and shares of its common stock, upon receipt of $25.0 million aggregate gross proceeds from sales of common stock to Lincoln Park under the 2022 Purchase Agreement.

On August 17, 2022, a registration statement (the “First Registration Statement”) was declared effective to cover the resale of up to 633,333 shares of the Company’s common stock comprised of (i) the 32,846 initial commitment shares, and (ii) up to 600,486 that the Company has reserved for issuance and sale to Lincoln Park under the 2022 Purchase Agreement from time to time from and after the date of the prospectus. The Company sold 527,166 shares of common stock to Lincoln Park in connection with the First Registration Statement.

On August 18, 2023, a second registration statement (the “Second Registration Statement”) was declared effective to cover the resale of up to an additional 1,500,000 shares of the Company’s common stock that the Company reserved for issuance and sale to Lincoln Park under the 2022 Purchase Agreement from time to time. The Company sold 150,000 shares of common stock to Lincoln Park in connection with the Second Registration Statement. The Company cannot sell more shares than registered under the Second Registration Statement under the 2022 Purchase Agreement without registering additional shares.

Actual sales of shares of common stock to Lincoln Park under the 2022 Purchase Agreement depend on a variety of factors to be determined by the Company from time to time, including, among others, market conditions, the trading price of the common stock and determinations by the Company as to the appropriate sources of funding for the Company and its operations. The net proceeds under the 2022 Purchase Agreement to the Company depend on the frequency and prices at which the Company sells shares of its common stock to Lincoln Park.

During the period from August 17, 2022 to December 31, 2022, the Company issued 266,666 shares of common stock under the 2022 Purchase Agreement for net proceeds of approximately $3.2 million. The Company issued 410,500 shares of common stock under the 2022 Purchase Agreement for net proceeds of approximately $1.0 million from January 1, 2023 to December 31, 2023. The Company did not issue any shares of common stock under the 2022 Purchase Agreement during the year ended December 31, 2024.

Share Repurchase Program and Treasury Stock

On October 31, 2023, the Company announced that its Board has approved a share repurchase program (the “Share Repurchase Program”), with authorization to repurchase up to $500,000 of the outstanding shares of the Company’s common stock. The Company funded repurchases under the Share Repurchase Program with available cash.

During the year

ended December 31, 2023, the Company purchased 78,559 shares of its common stock for approximately $0.1 million as treasury stock. The Company purchased 179,866 shares of its common stock for approximately $0.4 million as treasury stock during the year ended December 31, 2024. As of December 31, 2024, no amount remained aut

horized

for repurchase.

- Definition

The entire disclosure for equity.

+ References

+ Details

License Agreements - Additional Information (Details) - USD ($) $ in Thousands	Mar. 29, 2020	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
License Agreement [Line Items]
Voting stock, value		$ 132	$ 6	$ 5
Nano Tx Licenses Agreement [Member]
License Agreement [Line Items]
License fee payment in cash	$ 400
Voting stock, value	$ 300
Percentage of non-dilutive monetary awards required to pay	15.00%
Accrued payments due to NanoTx		$ 300	$ 1,000

Term Loan Obligations	12 Months Ended
Term Loan Obligations	Dec. 31, 2024
Debt Disclosure [Abstract]
Term Loan Obligations	9. Term Loan Obligations On May 29, 2015, the Company entered into the Loan and Security Agreement (the “Loan and Security Agreement”), pursuant to which Oxford Finance, LLC (“Oxford”) funded an aggregate principal amount of $17.7 million (the “Term Loan”), subject to the terms and conditions set forth in the Loan and Security Agreement. Pursuant to the Loan and Security Agreement, as amended, the Company made interest only payments through May 1, 2021, and thereafter was required to make payments of principal and accrued interest in equal monthly installments sufficient to amortize the Term Loan through June 1, 2024, the maturity date. On June 3, 2024, the Company paid off the Term Loan by making a final payment in an aggregate amount equal to approximately $3.3 million, which included both the balance of outstanding principal and interest and the final payment fee due. The repayment in full of the Term Loan terminated Oxford’s security interest in the Company’s existing and after-acquired assets, as well as all other restrictions and covenants under the Term Loan.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
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-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
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-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (d)
-Publisher FASB
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
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-Publisher FASB
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

+ Details

Summary of Significant Accounting Policies	9 Months Ended	12 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2025	Dec. 31, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Significant Accounting Policies The Company’s significant accounting policies are disclosed in its Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC and have not materially changed during the nine months ended September 30, 2025. The Company believes that the disclosures provided here are adequate to make the information presented not misleading when these unaudited condensed consolidated financial statements are read in conjunction with the audited consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, filed with the Securities and Exchange Commission on March 31, 2025. Use of Estimates The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions affecting the financial statements and the accompanying notes. The Company’s most significant estimates and critical accounting policies involve estimating the fair value of its derivative instruments, reviewing assets for impairment and determining the assumptions used in measuring stock-based compensation expense. Grant Revenue Recognition In applying the provisions of Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”), the Company has determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer”, as defined by ASC 606, as the Company does not consider there to be a transfer of control of goods or services. With respect to each grant, the Company determines if it has a collaboration in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, the Company applies International Accounting Standards No. 20 (“IAS 20”), Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the contract. The Company also considers the guidance in ASC Topic 730, Research and Development, which requires an assessment, at the inception of each grant, of whether each grant agreement is a liability. If the Company is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred. Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date. Warrants Warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement in accordance with applicable accounting guidance provided in ASC Topic 815, Derivatives and Hedging. Equity-classified instruments are recorded in additional paid-in capital at issuance and are not subject to remeasurement. Liability-classified warrants are recorded at fair value at each reporting period with any change in fair value recognized as a component of change in fair value of derivative liabilities in the condensed consolidated statements of operations. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants. Available-for-Sale Securities The Company’s available-for-sale securities consist of U.S. government and agency securities and bonds. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the condensed consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (expense). At each balance sheet date, the Company assesses available-for-sale securities in an unrealized loss position to determine whether the decline in fair value below amortized cost is a result of credit losses or other factors, whether the Company expects to recover the amortized cost of the security, the Company’s intent to sell and if it is more likely than not that the Company will be required to sell the securities before the recovery of amortized cost. The Company records changes in allowance for expected credit loss in other income (expense). There has been no allowance for expected credit losses recorded during any of the periods presented. Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the condensed consolidated statements of operations. Recently Issued Accounting Pronouncements In December 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) No. 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosure. This ASU includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The ASU is effective for years beginning after December 15, 2024, but early adoption is permitted. This ASU should be applied on a prospective basis, although retrospective application is permitted. The Company adopted this ASU as of January 1, 2025 which did not have a material impact on the Company’s consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03 Income Statement (Topic 220): Reporting Comprehensive Income - Expense Disaggregation Disclosures, which requires an entity to disclose on an annual and interim basis, disaggregated information about specific income statement expense categories. The guidance should be applied prospectively with the option to apply the standard retrospectively. The standard becomes effective for the annual period starting on January 1, 2027 and interim periods starting on January 1, 2028. The Company is in the process of analyzing the impact that the adoption of ASU 2024-03 will have on its disclosures.	2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions affecting the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting period. The most significant estimates and critical accounting policies involve reviewing assets for impairment, and determining the assumptions used in measuring share-based compensation expense and warrant liability. Actual results could differ from these estimates. Management’s estimates and assumptions are reviewed regularly, and the effects of revisions are reflected in the financial statements in the periods they are determined to be necessary. Cash and cash equivalents The Company considers all highly liquid investments with maturities of three months or less at the time of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking, savings accounts and money market accounts. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institution in which those deposits are held. Financial Instruments Financial instruments include cash equivalents, other current assets, accounts payable, accrued expenses, other liabilities and long-term debt. The carrying values of cash equivalents, other current assets, accounts payable, accrued expenses and other liabilities generally approximate fair value due to the short-term nature of these instruments. Based on level 3 inputs and the borrowing rates currently available for loans with similar terms, the Company believes the fair value of the long-term debt is materially consistent with its carrying value. Property and Equipment Property and equipment are stated at cost, net of accumulated depreciation . Depreciation expense, which includes the amortization of capitalized leasehold improvements, is provided for on a straight-line basis over the estimated useful lives of the assets, or the life of the lease, whichever is shorter, and range from three to five years. When assets are sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and the resulting gain or loss, if any, is included in operations. Maintenance and repairs are charged to operations as incurred. Impairment The Company assesses its property and equipment and intangible assets for potential impairment when there is a change in circumstances that indicates carrying values of assets may not be recoverable. Such long-lived assets are deemed to be impaired when the undiscounted cash flows expected to be generated by the asset (or asset group) are less than the asset’s carrying amount. Any required impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value and would be recorded as a reduction in the carrying value of the related asset and a charge to operating expense. The Company recognized no impairment losses during any of the periods presented in these financial statements. Goodwill The Company’s goodwill represents the excess of the cost over the fair value of net assets acquired from its business combinations. The determination of the value of goodwill arising from business combinations requires extensive use of accounting estimates and judgments to allocate the purchase price to the fair value of the net tangible and intangible assets acquired. Goodwill is not amortized; however, it is assessed for impairment using fair value measurement techniques on an annual basis or more frequently if facts and circumstance warrant such a review. Goodwill is considered to be impaired if the Company determines that the carrying value of the reporting unit exceeds its fair value. The Company performs its impairment test annually during the fourth quarter by comparing the Company’s estimated fair value, calculated from the Company’s market capitalization, to its carrying amount. The Company’s annual evaluation for impairment of goodwill consists of one reporting unit. The Company completed its most recent annual evaluation for impairment as of December 31, 2024, when the Company had stockholders’ deficit within its sole reporting unit of approximately $8.9 million, and concluded that no impairment existed. Grant Revenue Recognition In applying the provisions of Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”), the Company has determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer,” as defined by ASC 606, as there is not considered to be a transfer of control of goods or services. With respect to the grant, the Company determines if it is a collaboration arrangement in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, the Company applies International Accounting Standards No. 20, Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the contract. The Company also considers the guidance in ASC Topic 730, Research and Development (“ASC 730”), which requires an assessment, at the inception of the grant, of whether the agreement is a liability. If the Company is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred. Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant Receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date. Research and Development Research and development expenditures, which are charged to operations in the period incurred, include costs associated with the design, development, testing and enhancement of the Company’s products, regulatory fees, the purchase of laboratory supplies, and pre-clinical and clinical studies as well as salaries and benefits for the Company’s research and development employees. Warrants Warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement in accordance with applicable accounting guidance provided in ASC Topic 815— Derivatives and Hedging . Equity-classified instruments are recorded in additional paid-in capital at issuance and are not subject to remeasurement. Liability-classified warrants are recorded at fair value at each reporting period with any change in fair value recognized as a component of change in fair value of warrants in the consolidated statements of operations. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants. Available-for-Sale Securities The Company’s available-for-sale securities consist of U.S. government and agency securities. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) within the consolidated statements of operations and comprehensive income/loss and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (loss). At each balance sheet date, the Company assesses available-for-sale securities in an unrealized loss position to determine whether the decline in fair value below amortized cost is a result of credit losses or other factors, whether the Company expects to recover the amortized cost of the security, the Company’s intent to sell and if it is more likely than not that the Company will be required to sell the securities before the recovery of amortized cost. The Company records changes in allowance for expected credit loss in other income (expense). There has been no allowance for expected credit losses recorded during any of the periods presented. Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the consolidated statements of operations and comprehensive income/loss. During the year ended December 31, 2024, the total unrealized gains and losses on the Company’s available-for-sale securities were immaterial, and not presented separately in the consolidated statement of operations. Deferred Financing Costs and Other Debt-Related Costs Deferred financing costs are capitalized, recorded as an offset to debt balances and amortized to interest expense over the term of the associated debt instrument using the effective interest method. If the maturity of the debt is accelerated because of default or early debt repayment, then the amortization would be accelerated. Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income (loss) in the years in which those temporary differences are expected to be recovered or settled. Due to our history of losses, a full valuation allowance has been recognized against our deferred tax assets. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. For the years ended December 31, 2024 and 2023, the Company has not recorded any interest or penalties related to income tax matters. The Company does not foresee any material changes to unrecognized tax benefits within the next twelve months. Share-Based Compensation The Company recognizes the fair value of all share-based payment awards in our statements of operations over the requisite vesting period of each award, which approximates the period during which the employee and non-employee director is required to provide service in exchange for the award. The Company estimates the fair value of these options using the Black-Scholes option pricing model using assumptions for expected volatility, expected term, and risk-free interest rate. Expected volatility is based primarily on historical volatility and is computed using daily pricing observations for recent periods that correspond to the expected term of the options. The expected term represents the period of time that options are expected to be outstanding. Because the Company does not have historical exercise behavior, it determines the expected life assumption using the simplified method which is an average of the contractual term of the option and its vesting period. The risk-free interest rate is the interest rate for treasury instruments with maturities that approximate the expected term. Segment Information For the years ended December 31, 2024 and 2023, the Company is managed as a single operating segment, and therefore reports its results in one operating segment. Loss Per Share Basic per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period increased to include, if dilutive, the number of additional common shares that would have been outstanding as calculated using the treasury stock method. Potential common shares were related entirely to outstanding but unexercised options, warrants and convertible preferred stocks for all periods presented. Concentration Risk Although the Company’s contracts with its vendors are not exclusive, the Company currently uses sole source providers for core materials used in its clinical trials. Recently Issued Accounting Pronouncements In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The new standard is intended to improve annual and interim reportable segment disclosure requirements regardless of number of reporting units, primarily through enhanced disclosures of significant expenses. The amendment requires public entities to disclose significant segment expenses that are regularly provided to the Company’s chief operating decision maker (“CODM”) and included within each reported measure of segment profit and loss. This update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years starting after December 15, 2024. This ASU must be applied retrospectively to all prior periods presented. Management adopted this ASU as of December 31, 2024 and included additional disclosures as required in the footnotes to this annual report on Form 10-K. In December 2023, the FASB issued ASU No. 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosure. This ASU includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The ASU is effective for years beginning after December 15, 2024, but early adoption is permitted. This ASU should be applied on a prospective basis, although retrospective application is permitted. Management does not expect the adoption of this ASU to have a material impact on the Company’s consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03 Income Statement (Topic 220): Reporting Comprehensive Income—Expense Disaggregation Disclosures, which requires an entity to disclose on an annual and interim basis, disaggregated information about specific income statement expense categories. The guidance should be applied prospectively with the option to apply the standard retrospectively. The standard becomes effective for the annual period starting on January 1, 2027 and interim periods starting on January 1, 2028. The Company is in the process of analyzing the impact that the adoption of ASU 2024-03 will have on its disclosures.

Fair Value Measurements - Summary of Key Inputs Used in Valuation of Liability Classified Warrants (Details) - Warrant Liability [Member]	Dec. 31, 2024	May 05, 2024
Expected Term [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Expected term	10 months 24 days	1 year 1 month 6 days
Expected Term [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Expected term	4 years 8 months 12 days	5 years
Common Stock Market Price [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	1.45
Common Stock Market Price [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		2.01
Common Stock Market Price [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		2.27
Risk-free Interest Rate [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	3.81	4.5
Risk-free Interest Rate [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	4.63	5.1
Volatility [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	92.2	117
Volatility [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	99.79	127.2

Biocept Asset Acquisition	9 Months Ended	12 Months Ended
Biocept Asset Acquisition	Sep. 30, 2025	Dec. 31, 2024
Asset Acquisition [Abstract]
Biocept Asset Acquisition	12. Biocept Asset Acquisition On April 26, 2024, the Company, after having its bid accepted by the United States Bankruptcy Court for the District of Delaware, acquired from Biocept, Inc. (“Biocept”), for a total cash payment of $400,000, substantially all of the right, title and interest in a cerebrospinal fluid cancer diagnostic portfolio (the “CNSide ® Platform”), including (i) intellectual property, (ii) inventory and raw materials, and (iii) data, information, results and reports pertaining to the completed and on-going clinical studies involving the use of the CNSide Platform (including, but not limited to, the FORESEE clinical study that was being conducted by Biocept), related to the development, making, selling, and exporting or importing of the CNSide proprietary cell enumeration test (the “CNSide Test”). The Company concluded that the acquisition of the Biocept assets was not a business combination, as Biocept did not meet the definition of a business in ASC 805, Business Combination. The Company accounted for the asset purchase transaction under the authoritative guidance for asset acquisitions, and allocated the costs of acquisition of approximately $45,000 among the assets acquired based on the relative fair value of such assets, which is predominately concentrated in the intellectual property acquired including patents and trademarks. The intangible assets acquired from Biocept are capitalized and amortized over a useful life of four years.	12. Biocept Asset Acquisitions On April 26, 2024, the Company, after having its bid accepted by the United States Bankruptcy Court for the District of Delaware, acquired from Biocept, for a total cash payment of $400,000, substantially all of the right, title and interest in a cerebrospinal fluid cancer diagnostic portfolio (the “CNSide TM Platform”), including (i) intellectual property, (ii) inventory and raw materials, and (iii) data, information, results and reports pertaining to the completed and on-going clinical studies involving the use of the CNSide TM Platform (including, but not limited to, the FORESEE clinical study that was being conducted by Biocept), related to the development, making, selling, and exporting or importing of the CNSide TM proprietary cell enumeration test (the “CNSide TM Test”). The Company concluded that the acquisition of the Biocept assets was not a business combination, as Biocept did not meet the definition of a business in ASC 805, Business Combination. The Company accounted for the asset purchase transaction under the authoritative guidance for asset acquisitions, and allocated the costs of acquisitions of approximately $45,000 among the assets acquired based on the relative fair value of such assets, which is predominately concentrated in the intellectual property acquired including patents and trademarks. The intangible assets acquired from Biocept are capitalized and amortized over a useful life of four years.

Submission	Jan. 09, 2026
Submission [Line Items]
Central Index Key	0001095981
Registrant Name	PLUS THERAPEUTICS, INC.
Form Type	S-1
Submission Type	S-1
Fee Exhibit Type	EX-FILING FEES
Offering Table N/A
Offset Table N/A
Combined Prospectus Table N/A	N/A

Composition of Certain Financial Statement Captions

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Composition Of Certain Financial Statement Captions [Abstract]

Composition of Certain Financial Statement Captions

9. Composition of Certain Financial Statement Captions

As of September 30, 2025 and December 31, 2024, other current assets were comprised of the following (in thousands):


	September 30, 2025		December 31, 2024
Prepaid services	$	551	$	87
Deferred costs (Note 8)		299		436
Prepaid insurance		135		559

Total other current assets	$	985	$	1,082

6. Composition of Certain Financial Statement Captions

Other Current Assets

As of December 31, 2024 and 2023, other current assets were comprised of the following (in thousands):


	December 31,
	2024		2023
Prepaid services	$	87	$	410
Deferred costs (Note 7)		436		234
Prepaid insurance		559		636

	$	1,082	$	1,280

Property and Equipment, net

As of December 31, 2024 and 2023, property and equipment, net, were comprised of the following (in thousands):


	December 31,
	2024			2023
Office and computer equipment	$	1,778		$	1,632
Leasehold improvements		1,810			1,810

		3,588			3,442
Less accumulated depreciation		(3,140	)		(2,536	)

	$	448		$	906

Depreciation expense totaled $0.6 million for each of the years ended December 31, 2024 and 2023, respectively.

Intangible Assets, net

As of December 31, 2024, intangible assets included the net book value of costs incurred for purchase of Biocept intellectual properties (Note 12) and software upgrades. Amortization expenses totaled $0.1 million for each of the years ended December 31, 2024 and 2023.

As of December 31, 2024 intangible assets, net, were comprised of the following (in thousands):


	December 31, 2024
	Gross Carrying Amount		Accumulated Amortization			Intangible Asset, Net
Software	$	221	$	(218	)	$	3
Intellectual Property		546		(80	)		466

Total intangible assets	$	767	$	(298	)	$	469

As of December 31, 2023 intangible assets, net, were comprised of the following (in thousands):


	December 31, 2023
	Gross Carrying Amount		Accumulated Amortization			Intangible Asset, Net
Software	$	221	$	(179	)	$	42

Total intangible assets	$	221	$	(179	)	$	42

As of December 31, 2024, future amortization expense on intangible assets is estimated to be as follows (in thousands):


Year Ending December 31,	Amount
2025		140
2026		136
2027		136
2028		57

Total future amortization expense	$	469

Accounts Payable and Accrued Expenses

As of December 31, 2024 and 2023, accounts payable and accrued expenses were comprised of the following (in thousands):


	December 31,
	2024		2023
Accounts payable	$	9,474	$	4,758
Accrued payroll and bonus		920		987
Accrued professional fees		236		128
Accrued vacation and compensation		356		370
Accrued R&D studies		185		388
Accrued interest		117		—

	$11,288		$6,631

Fair Value Measurements - Schedule of Change in Fair Value of Liability (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	$ 0	$ 0
Issuance	16,010	10,854
Change in fair value	3,147	(5,654)
Settlement	(1,389)
Modification and extinguishment	(6,801)
Reclassified to equity	(10,967)
Ending balance as of September 30, 2025	0	0
Convertible Notes [Member] \| Funding Notes [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	0
Issuance	3,968
Change in fair value	(265)
Settlement	(3,703)
Ending balance as of September 30, 2025	0	0
Convertible Notes [Member] \| Exchange Notes [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	0
Issuance	3,763
Change in fair value	(251)
Settlement	(3,512)
Ending balance as of September 30, 2025	0	0
February 2025 Warrants [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	0
Issuance	2,762
Change in fair value	(2,231)
Settlement	(531)
Modification and extinguishment	0
Reclassified to equity	0
Ending balance as of September 30, 2025	0	0
March 2025 Series A Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	0
Issuance	2,005
Change in fair value	335
Settlement	0
Modification and extinguishment	(2,340)
Reclassified to equity	0
Ending balance as of September 30, 2025	0	0
March 2025 Series B Warrants [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	0
Issuance	11,243
Change in fair value	5,043
Settlement	(858)
Modification and extinguishment	(4,461)
Reclassified to equity	(10,967)
Ending balance as of September 30, 2025	$ 0	$ 0

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Cash flows used in operating activities:
Net loss	$ (16,673)	$ (9,075)	$ (12,978)	$ (13,316)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	300	524	723	628
Amortization of deferred financing costs and debt discount		20	20	190
Stock-based compensation expense	827	422	550	569
Noncash financing expenses	3,061	3,545	3,545
Change in fair value of derivative instruments	2,631	(5,654)
Common stock issued for research and development				75
Accretion of discount on short-term investments	(19)	(70)	(111)
Reduction in the carrying amount of operating lease right-of-use assets	53	96	129	117
Gain on sale of assets	(16)			2
Increases (decreases) in cash caused by changes in operating assets and liabilities:
Other assets	635	704
Grant receivable			(571)
Accounts payable and accrued expenses	(6,308)	1,326	4,702	(3,677)
Change in operating lease liabilities	(54)	(97)	(130)	(117)
Deferred grant liability	1,045	(1,084)	(997)	281
Other assets			218	2,397
Change in fair value of warrants	800		(5,654)
Net cash used in operating activities	(14,518)	(9,343)	(10,554)	(12,851)
Cash flows used in investing activities:
Purchases of property and equipment	(37)	(135)	(146)	(160)
Proceeds from sale of property and equipment	30
Purchase of short-term investments	(11,068)	(7,145)	(15,590)
Redemption of short-term investments	11,305	3,650	12,170
Purchase of intangible assets	(7)	(545)	(545)
Net cash provided by (used in) investing activities	223	(4,175)	(4,111)	(160)
Cash flows provided by financing activities:
Principal payments of term loan obligation		(3,996)	(3,996)	(1,608)
Proceeds from credit facility		3,292	3,292
Repayment of credit facility	(3,292)
Payment of financing costs	(2,250)
Proceeds from issuance of notes payable and warrants	3,738
Repayment of notes payable	(3,703)
Purchase of treasury stock		(374)	(374)	(126)
Proceeds from sale of common stock, pre-funded warrants and warrants	15,927	7,265
Proceeds from sale of common stock under Lincoln Park Purchase Agreement	19,612
Payment to investors pursuant to Letter Agreement (Note 13)	(2,293)
Offering costs for sale of common stock	(231)			(348)
Proceeds from sale of common stock warrants and pre-funded warrants, net			7,265
Proceeds from sale of common stock, net of offering costs of $0.2 million				5,527
Net cash provided by financing activities	27,508	6,187	6,187	3,445
Net increase (decrease) in cash and cash equivalents	13,213	(7,331)	(8,478)	(9,566)
Cash and cash equivalents at beginning of period	76	8,554	8,554	18,120
Cash and cash equivalents at end of period	13,289	1,223	76	8,554
Cash paid during period for:
Interest	539	$ 32	$ 32	222
Supplemental schedule of non-cash investing and financing activities:
Unpaid liability to investors pursuant to Letter Agreement (Note 13)	6,391
Exchange of warrants for notes payable	3,694
Redemption of notes by issuance of common stock, pre-funded warrants and warrants	3,512
Unpaid offering cost	$ 252			174
Common stock issued in payment for in process research and development				75
Right-of-use assets acquired by assuming operating lease liabilities				$ 71

Segment Information (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Segment Reporting [Abstract]

Schedule of Segment Expenses


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(in thousands)	2025		2024		2025		2024
Research and development
Clinical, development and licensing expenses	$	1,362	$	873	$	2,698	$	3,548
Personnel related expenses		434		806		1,316		2,435
Professional fees		391		830		737		1,412
Facility and other overhead expenses		249		349		687		999

Total research and development		2,436		2,858		5,438		8,394
General and administrative
Personnel related expenses		1,309		705		3,256		2,052
Professional fees		1,744		1,281		3,748		3,585
Facility and other overhead expenses		390		411		960		1,176

Total general and administrative	$	3,443	$	2,397	$	7,964	$	6,813


(in thousands)	Twelve Months Ended December 31, 2024		Twelve Months Ended December 31, 2023
Research and development
Clinical, development and licensing expenses	$	4,549	$	5,062
Personnel related expenses		3,026		2,852
Professional fees		1,733		635
Facility and other overhead expenses		1,272		1,141

Total research and development		10,580		9,690
General and administrative
Personnel related expenses		3,454		3,006
Professional expenses		4,828		3,870
Facility and other overhead expenses		1,657		1,668

Total general and administrative	$	9,939	$	8,544

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2024
Retirement Benefits [Abstract]
Employee Benefit Plan	14. Employee Benefit Plan The Company implemented a 401(k) retirement savings and profit sharing plan (the “Plan”) effective January 1, 1999. During 2022, the Company commenced safe harbor matching contribution for up to 4% of eligible employee contributions. Total matching contribution under the Plan amounted to approximately $138,000 and $107,000 for the year ended December 31, 2024 and 2023, respectively.

Share-based Compensation - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares to be issued (in shares)		10,800,137	506,127
Stock option contractual term		10 years	10 years
Stock option vesting percentage		25.00%	25.00%
Stock options exercised			$ 0	$ 0
Dividend yield assumed			0
Total unamortized compensation cost related to outstanding unvested stock options and restricted stock awards	$ 5,400,000	$ 5,400,000	$ 700,000
Weighted average period for recognition of cost		3 years 3 months 14 days	2 years 9 months 18 days
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unamortized compensation cost related to outstanding unvested stock options and restricted stock awards	$ 1,500,000	$ 1,500,000
Weighted average period for recognition of cost	2 years 9 months
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting period		2 years	2 years
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting period		4 years	4 years
2015 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Securities remaining and available for future issuances (in shares)	76,025	76,025	62,908
2020 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Securities remaining and available for future issuances (in shares)	10,005,151	10,005,151	692,596
Common stock shares to be issued (in shares)	20,000,000	21,303,334	3,550,000

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2025

Stockholders Equity Note [Abstract]

Summary of Warrants Outstanding

As of September 30, 2025, the Company had the following warrants outstanding:


	September 30, 2025
May 2024 Series A Warrants		48,285
May 2024 Series B Warrants		3,093,708
March 2025 Pre-Funded Warrants		2,611,809

Total		5,753,802

Segment Information

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Segment Reporting [Abstract]

Segment Information

15. Segment Information

The Company operates under one reportable business segment to advance the development, manufacturing and commercialization of complex and innovative treatments for patients battling cancer and other life-threatening diseases. The determination of a single reportable business segment is consistent with the consolidated financial information regularly provided to the Company’s CODM. All of the Company’s long-term assets and operations are located in the United States, and the measure of segment assets is reported on the condensed consolidated balance sheets as total assets. The Company’s CODM is its

Chief Executive Officer

, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources, and

evaluating

financial performance, including comparing actual results to budgets and forecasts to assess variances, identify trends, and guide strategic planning.

In addition to the significant expense categories included within the consolidated statements of operations, the below disaggregated amounts comprise significant research and development and general and administrative expenses. These expenses consist of (1) clinical, manufacturing and research contracts for research and development programs, (2) personnel-related expenses, including salaries, benefits and stock-based compensation, (3) professional fees, including third-party costs for goods and services such as lab supplies and contract research, and legal and other professional expenses, and (4) facility and other overhead expenses, including depreciation, occupancy, travel, insurance and other costs. Depreciation and amortization expense is consistent with those presented in the condensed consolidated statements of cash flows.


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(in thousands)	2025		2024		2025		2024
Research and development
Clinical, development and licensing expenses	$	1,362	$	873	$	2,698	$	3,548
Personnel related expenses		434		806		1,316		2,435
Professional fees		391		830		737		1,412
Facility and other overhead expenses		249		349		687		999

Total research and development		2,436		2,858		5,438		8,394
General and administrative
Personnel related expenses		1,309		705		3,256		2,052
Professional fees		1,744		1,281		3,748		3,585
Facility and other overhead expenses		390		411		960		1,176

Total general and administrative	$	3,443	$	2,397	$	7,964	$	6,813

17. Segment Information

Chief Executive Officer

, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources, and

evaluating

financial performance, including comparing actual results to budgets and forecasts to assess variances, identify trends, and guide strategic planning.

In addition to the significant expense categories included within the consolidated statements of operations, the below disaggregated amounts comprise significant research and development and general and administrative expenses. These expenses consist of (1) clinical, manufacturing and research contracts for research and development programs, (2) personnel-related expenses, including salaries, benefits and share-based compensation, (3) professional fees, including third-party costs for goods and services such as lab supplies and contract research, and legal and other professional expenses, and (4) facility and other overhead expenses, including depreciation, occupancy, travel, insurance and other costs.


(in thousands)	Twelve Months Ended December 31, 2024		Twelve Months Ended December 31, 2023
Research and development
Clinical, development and licensing expenses	$	4,549	$	5,062
Personnel related expenses		3,026		2,852
Professional fees		1,733		635
Facility and other overhead expenses		1,272		1,141

Total research and development		10,580		9,690
General and administrative
Personnel related expenses		3,454		3,006
Professional expenses		4,828		3,870
Facility and other overhead expenses		1,657		1,668

Total general and administrative	$	9,939	$	8,544

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

Fair Value Measurements - Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value (Details)	Jun. 17, 2025	Mar. 04, 2025	Feb. 13, 2025
March 2025 Series A and Series B Warrants \| Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	3.91		3.98
March 2025 Series A and Series B Warrants \| Remaining Term [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Remaining term (years)	4 years 10 months 24 days		6 years 1 month 6 days
March 2025 Series A and Series B Warrants \| Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input	135.6		123.7
March 2025 Series B Warrants [Member] \| Interest Rate [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		3.85
March 2025 Series B Warrants [Member] \| Interest Rate [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		4.06
March 2025 Series B Warrants [Member] \| Remaining Term [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Remaining term (years)		4 years 10 months 24 days
March 2025 Series B Warrants [Member] \| Remaining Term [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Remaining term (years)		5 years
March 2025 Series B Warrants [Member] \| Volatility [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		133.9
March 2025 Series B Warrants [Member] \| Volatility [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		135.8
February 2025 Warrants [Member] \| Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		4.3	4.3
February 2025 Warrants [Member] \| Remaining Term [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Remaining term (years)		4 years 11 months 12 days	5 years
February 2025 Warrants [Member] \| Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		102.1	98.5
February 2025 Warrants [Member] \| Fair Value of Common Stock [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, Measurement input		0.3	1.2

Composition of Certain Financial Statement Captions - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Composition Of Certain Financial Statement Captions [Abstract]
Depreciation expense	$ 0.6	$ 0.6
Amortization	$ 0.1	$ 0.1

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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+ Details

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Income Taxes [Line Items]
Provision or benefit for income taxes	$ 0	$ 0
Income Tax Contingency [Abstract]
Valuation allowance	22,600,000
Increase (decrease) in valuation allowance	$ 3,100,000
Cumulative change in ownership	50.00%
Period of net operating loss and R&D tax credit carry forwards to offset future taxable income	3 years
Liability for uncertain tax positions	$ 0	$ 0
Period for material changes of liability for uncertain tax benefits	12 months
Interest related to unrecognized tax benefits in interest expense and penalties	$ 0
Federal [Member]
Income Tax Contingency [Abstract]
Tax loss carryforwards	$ 72,600,000
Net operating loss carryforwards, Expire date	begin to expire in 2037
Federal tax carry forward	$ 1,900,000
Tax credit carryforward, expiration date	begin to expire in 2039
Net operating losses	$ 69,200,000
Federal [Member] \| Maximum [Member]
Income Tax Contingency [Abstract]
Percentage of federal net operating losses used to offset of future taxable income	80.00%
State [Member]
Income Tax Contingency [Abstract]
Tax loss carryforwards	$ 3,300,000
Net operating loss carryforwards, Expire date	2044
State tax credit carryforwards	$ 200,000
Tax credit carryforward, expiration date	begin to expire in 2039

Liquidity and Going Concern	9 Months Ended
Liquidity and Going Concern	Sep. 30, 2025
Liquidity [Abstract]
Liquidity and Going Concern	3. Liquidity and Going Concern The Company incurred a net loss of $16.7 million for the nine months ended September 30, 2025. The Company had an accumulated deficit of $510.2 million as of September 30, 2025. Additionally, the Company used net cash of $14.5 million to fund its operating activities for the nine months ended September 30, 2025. To date, the Company’s operating losses have been funded primarily from outside sources of invested capital from issuance of its common stock, preferred stock, convertible notes and warrants, proceeds from its term loan, line of credit and grant funding. However, the Company has had, and will continue to have, an ongoing need to raise additional cash from outside sources to fund its future clinical development programs, launch the CNSide Test, and fund other operations. There can be no assurance that the Company will be able to continue to raise additional capital in the future. The Company’s inability to raise additional cash would have a material and adverse impact on its operations. These factors raise substantial doubt about the Company’s ability to continue as a going concern. As disclosed in more detail in Note 13, the Company has entered into various financing agreements and raised capital by issuing convertible notes, its common stock, preferred stock and warrants to purchase its common stock. Nasdaq Listing Compliance On March 8, 2024, the Company received a written notice (the “Notice”) from the Listing Qualifications staff (the “Staff”) of The Nasdaq Stock Market LLC (the “Nasdaq)”), notifying the Company that it no longer complied with the requirement under Nasdaq Listing Rule 5550(b)(1) to maintain a minimum of $2.5 million in stockholders’ equity (the “Minimum Stockholders’ Equity Requirement”) for continued listing on The Nasdaq Capital Market or the alternative requirements of having a market value of listed securities of $35 million or net income from continuing operations of $500,000 in the most recently completed fiscal year or two of the last three most recently completed fiscal years. On September 5, 2024, Nasdaq notified the Company that it had not regained compliance with Nasdaq Listing Rule 5550(b)(1). The Company requested a hearing before the Nasdaq hearing panel, and on October 30, 2024, the Company received a decision from the panel, notifying the Company that it had until March 4, 2025, to demonstrate compliance with the Minimum Stockholders’ Equity Requirement. On March 7, 2025, the Company received notification from Nasdaq that it had regained compliance with the Minimum Stockholders’ Equity Requirement. Pursuant to Nasdaq Listing Rule 5815(d)(4)(B), the Company is subject to a Mandatory Panel Monitor until March 7, 2026. If the Staff finds the Company again out of compliance with the Minimum Stockholders’ Equity Requirement before that date, the Company would not be permitted to provide the Staff with a plan of compliance with respect to that deficiency and the Staff would not be permitted to grant additional time for the Company to regain compliance with respect to that deficiency, nor would the Company be afforded an applicable cure or compliance period. Instead, the Staff would issue a “Delist Determination Letter” and the Company would have an opportunity to request a Nasdaq hearing panel regarding its continued listing. Furthermore, on May 16, 2025, the Company received notice from Nasdaq that, because the closing bid price for the Company’s common stock had fallen below $1.00 per share for 30 consecutive business days, the Company no longer complied with the minimum bid price requirement pursuant to Nasdaq Listing Rule 5550(a)(2) (the “Minimum Bid Requirement”). Nasdaq’s Minimum Bid Requirement notice has no immediate effect on the listing or trading of the Company’s common stock. Pursuant to Nasdaq Listing Rule 5810(c)(3)(A), the Company is provided an initial compliance period of 180 calendar days, or until November 12, 2025, to regain compliance with the Minimum Bid Requirement. To regain compliance, the closing bid price of the Company’s common stock must meet or exceed $1.00 per share for a minimum of 10 consecutive business days prior to November 12, 2025. If the Company does not achieve compliance with the Minimum Bid Requirement by November 12, 2025, the Company may be eligible for an additional 180 calendar days to regain compliance. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other Nasdaq initial listing standards, with the exception of the Minimum Bid Requirement, and provide written notice of its intention to cure the minimum bid price deficiency during the second compliance period by effecting a reverse stock split if necessary. If the Staff determines that the Company will not be able to cure the deficiency, or if the Company is otherwise not eligible for such additional compliance period, Nasdaq will provide notice that the Company’s common stock will be subject to delisting. In the event the Company receives notice that its common stock is being delisted, Nasdaq rules permit the Company to appeal any delisting determination by the Staff. On May 2, 2025, the stockholders granted discretionary authority to the Company’s board of directors to (i) amend the Company’s Certificate of Incorporation to combine outstanding shares of the Company’s common stock into a lesser number of outstanding shares, or a “reverse stock split,” at a specific ratio within a range of one-for twenty five ( 1-for-25 ) to a maximum of one-for-two hundred fifty (1-for-250), with the exact ratio to be determined by the board of directors in its sole discretion; and (ii) effect the reverse stock split, if at all, within twelve (12) months of the date the proposal is approved by stockholders. In addition, on August 7, 2025, the stockholders granted discretionary authority to the Company’s board of directors to (i) amend the Company’s Certificate of Incorporation to combine outstanding shares of the Company’s common stock into a lesser number of outstanding shares, or a “reverse stock split,” at a specific ratio within a range of one-for two (1-for-2) to a maximum of one-for-two hundred fifty (1-for-250), with the exact ratio to be determined by the board of directors in its sole discretion; and (ii) effect the reverse stock split, if at all, within twelve (12) months of the date the proposal is approved by stockholders. On June 3, 2025, the Staff notified the Company that it was not in compliance with the Minimum Stockholders’ Equity Requirement (the “June 3 Letter”). The Company reported stockholders’ equity (deficit) of ($23,641,000) in its Quarterly Report on Form 10-Q for the period ended March 31, 2025, and, as a result, did not satisfy the Minimum Stockholders’ Equity Requirement pursuant to Listing Rule 5550(b)(1). As a result, the Staff determined to delist the Company’s securities from Nasdaq, unless the Company timely requests an appeal of the Staff’s determination to a Hearings Panel (the “Panel”), pursuant to the procedures set forth in the Nasdaq Listing Rule 5800 Series. The Company must request a hearing no later than 4:00 p.m. Eastern Time on June 10, 2025. The Company timely requested a hearing, which hearing took place as scheduled on July 15, 2025. On July 22, 2025, the Panel issued a decision (the “July 2025 Decision”) granting the Company’s request for continued listing on Nasdaq, subject to the Company demonstrating compliance with (1) the Minimum Stockholders’ Equity Requirement pursuant to Listing Rule 5550 (b)(1) by August 14, 2025 by filing a timely public disclosure describing the transactions undertaken by the Company to achieve compliance and demonstrate long-term compliance of the Minimum Stockholders’ Equity Requirement, and by providing an indication of its equity following those transactions, with the option by including in the public filing a balance sheet not older than 60 days with pro forma adjustments for any significant transactions or events occurring on or before the report date; and (2) the Minimum Bid Requirement by September 8, 2025 . On August 22, 2025, the Company received a letter (the “August 2025 Letter”) from Nasdaq confirming its compliance with Nasdaq Listing Rule 5550(b). Specifically, the August 2025 Letter confirmed that the Company was in compliance with both (1) the Market Value of Listing Securities standard under 5550(b)(2), which requires certain companies to maintain a market value of listed securities of at least $35 million as well as compliance with (2) the alternative stockholders’ equity threshold under 5550(b)(1) or the Minimum Stockholders’ Equity Requirement. Accordingly, the Company satisfied two alternative criteria under Nasdaq Listing Rule 5550. As a result of such compliance, Nasdaq permitted the Company the remainder of the previously announced grace period to regain compliance with the $1.00 bid price rule under Nasdaq Listing Rule 5550(a)(2), through November 12, 2025. Nasdaq previously required that the Company remedy the bid price deficiency by September 8, 2025, a deadline that no longer applies. The August 2025 Letter also provided that, solely with respect to the Equity Standard, the Company remains subject to a one-year panel monitoring period, through August 22, 2026. If, within that one-year monitoring period, the Staff determines that the Company no longer satisfies the Equity Standard (and the Company is not then in compliance with one of the alternative standards under Rule 5550(b)), the Company will not be permitted to provide the Staff with a plan of compliance and the Staff is not permitted to grant additional time to regain compliance with the Equity Standard nor will the Company be afforded an applicable cure or compliance period. Instead, the Staff will issue a delist determination letter, and the Company will have an opportunity to request a new hearing before the Nasdaq Hearings Panel, which request would stay any further action by the Staff pending the ultimate outcome of the hearing. The Company continues to seek additional capital from other financing alternatives and other sources in order to ensure adequate funding is available to allow the Company to continue research and product development activities. If sufficient capital is not raised, the Company will at a minimum need to significantly reduce or curtail its research and development and other operations, and this would negatively affect its ability to achieve corporate growth goals. Should the Company fail to raise additional cash, it would have a material adverse impact on its operations. The accompanying condensed consolidated financial statements have been prepared assuming the Company will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to its ability to continue as a going concern.

Grant Revenue	9 Months Ended	12 Months Ended
Grant Revenue	Sep. 30, 2025	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Grant Revenue	7. Grant Revenue CPRIT Grant On September 19, 2022, the Company entered into that certain Cancer Research Grant Contract (the “CPRIT Contract”), effective as of August 31, 2022, with the Cancer Prevention and Research Institute of Texas (“CPRIT”), pursuant to which CPRIT provides the Company with a CPRIT Grant (“CPRIT Grant”) over a three-year period to fund the continued development of REYOBIQ TM for the treatment of patients with leptomeningeal metastases. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQ based on specific dollar thresholds and tiered low single digit royalty rates until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. The CPRIT Contract will terminate on February 28, 2026, unless terminated earlier by (a) the mutual written consent of all parties to the CPRIT Contract, (b) CPRIT for an event of default by the Company, (c) CPRIT, if the funds allocated to the CPRIT Grant become legally unavailable during the term of the CPRIT Contract and CPRIT is unable to obtain additional funds for such purposes, and (d) the Company for convenience. CPRIT may require the Company to repay some or all of the disbursed CPRIT Grant proceeds (with interest not to exceed 5% annually) in the event of the early termination of the CPRIT Contract by CPRIT for an event of default by the Company or by the Company for convenience, or if the Company relocates its principal place of business outside of the state of Texas during the CPRIT Contract term or within three years after the final payment of the grant funds. The Company retains ownership over any intellectual property developed under the CPRIT Contract (each, a “Project Result”). With respect to non-commercial use of any Project Result, the Company granted to CPRIT a nonexclusive, irrevocable, royalty-free, perpetual, worldwide license with right to sublicense any necessary additional intellectual property rights to exploit all Project Results by CPRIT, other governmental entities and agencies of the State of Texas, and private or independent institutions of higher education located in Texas, for education, research and other non-commercial purposes. The Company recognized $1.4 million and $3.8 million, and $1.5 million and $4.4 million in grant revenue from the CPRIT Contract during the three and nine months ended September 30, 2025 and 2024, respectively. As of September 30, 2025 and December 31, 2024, the Company had nil and $0.6 million, respectively, of grant revenue receivable related to the CPRIT Grant. As of September 30, 2025 and December 31, 2024, the Company had $1.1 million and nil of deferred grant liability related to the CPRIT Grant. Department of Defense Award Effective September 1, 2024, the Company entered into an agreement with the Department of Defense office of the Congressionally Directed Medical Research Programs to receive a $3.0 million award for research and development purposes (“DoD Award”) over a three year period. The DoD Award will be used to support the planned expansion of the Company’s clinical trial for pediatric brain cancer. On October 4, 2024, the Company received its first payment under the DoD Award in the amount of $ 0.9 million, which was recorded as deferred grant liability as of September 30, 2025 and December 31, 2024. As of September 30, 2025 and December 31, 2024, no amount of grant revenue was recognized related to the DoD Award.	11. Grant Revenue CPRIT Grant On September 19, 2022, the Company entered into that certain Cancer Research Grant Contract (the “CPRIT Contract”), effective as of August 31, 2022, with the Cancer Prevention and Research Institute of Texas (“CPRIT”), pursuant to which CPRIT provides the Company with a CPRIT grant (“CPRIT Grant”) over a three-year period to fund the continued development of REYOBIQ ™ for the treatment of patients with leptomeningeal metastases. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQ ™ based on specific dollar thresholds and tiered low single digit royalty rates until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. The CPRIT Contract will terminate on August 30, 2025, unless terminated earlier by (a) the mutual written consent of all parties to the CPRIT Contract, (b) CPRIT for an event of default by the Company, (c) CPRIT, if the funds allocated to the CPRIT Grant become legally unavailable during the term of the CPRIT Contract and CPRIT is unable to obtain additional funds for such purposes, and (d) the Company for convenience. CPRIT may require the Company to repay some or all of the disbursed CPRIT Grant proceeds (with interest not to exceed 5% annually) in the event of the early termination of the CPRIT Contract by CPRIT for an event of default by the Company or by the Company for convenience, or if the Company relocates its principal place of business outside of the state of Texas during the CPRIT Contract term or within three years after the final payment of the grant funds. The Company retains ownership over any intellectual property developed under the CPRIT Contract (each, a “Project Result”). With respect to non-commercial use of any Project Result, the Company granted to CPRIT a nonexclusive, irrevocable, royalty-free, perpetual, worldwide license with right to sublicense any necessary additional intellectual property rights to exploit all Project Results by CPRIT, other governmental entities and agencies of the State of Texas, and private or independent institutions of higher education located in Texas, for education, research and other non-commercial purposes. The Company recognized $5.8 million and $4.9 million in grant revenue from the CPRIT Contract during the years ended December 31, 2024 and 2023, respectively. As of December 31, 2024, the Company had $0.6 million of grant revenue receivable related to the CPRIT Grant. As of December 31, 2023, the Company had $1.9 million of deferred CPRIT grant revenue. In February 2025, the Company received $2.0 million under the CPRIT Contract. Department of Defense Award Effective September 1, 2024, the Company entered into an agreement with the Department of Defense office of the Congressionally Directed Medical Research Programs to receive a $3.0 million award for research and development purposes (“DoD Award”) over a three year period. The DoD Award will be used to support the planned expansion of the Company’s clinical trial for pediatric brain cancer. On October 4, 2024, the Company received its first payment under the DoD Award in the amount of $0.9 million, which was recorded as deferred grant liability as of December 31, 2024. As of December 31, 2024, no grant revenue has been recognized related to the DoD Award.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

Commitments and Contingencies - Additional Information (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023	Nov. 05, 2024	Jul. 01, 2023	Mar. 31, 2023
Recorded Unconditional Purchase Obligation [Line Items]
Operating leases expiry year		2025
Lease liability		$ 75,000
Operating lease right-of-use assets	$ 20,000	$ 73,000	$ 202,000
Operating lease, weighted average discount rate		11.60%
Operating lease, weighted average remaining term		10 months 24 days
Rent expense		$ 200,000	$ 200,000
Pre-clinical Research Study Obligations [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Contractual obligation	$ 0	$ 0
Manufacturing Agreement with SpectronRX
Recorded Unconditional Purchase Obligation [Line Items]
Initial commitment fee				$ 300,000
Charlottesville [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Lessee, operating lease, term of contract		12 months
Lessee, operating lease, existence of option to extend [true false]		true
Lessee, operating lease, option to extend	The Charlottesville Lease expires on	The Charlottesville Lease has a term of 12 months and the Company has the ability to renew for three additional one-year periods.
Lessee, operating lease, renewal term		1 year
Lease liability						$ 80,000
Operating lease discount rate					13.47%	12.76%
Operating lease right-of-use assets					$ 19,000
Operating leases, expiration date	Mar. 31, 2026

License Agreements	9 Months Ended	12 Months Ended
License Agreements	Sep. 30, 2025	Dec. 31, 2024
License Agreement [Abstract]
License Agreements	11. License Agreements UT Health Science Center at San Antonio (“UTHSCSA”) License Agreement On December 31, 2021, the Company entered into a Patent and Know-How License Agreement (the “UTHSCSA License Agreement”) with The University of Texas Health Science Center at San Antonio (“UTHSCSA”), pursuant to which UTHSCSA granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of biodegradable alginate microspheres (“BAM”) containing nanoliposomes loaded with imaging and/or therapeutic payloads. NanoTx License Agreement On March 29, 2020, the Company and NanoTx, Corp. (“NanoTx”) entered into a Patent and Know-How License Agreement, pursuant to which NanoTx granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of radiolabeled nanoliposomes. The transaction terms included an upfront payment of $0.4 million in cash and $0.3 million in the Company’s voting stock. The transaction terms also included success-based milestone and royalty payments contingent on key clinical, regulatory and sales milestones, as well as the requirement to pay 15% of any non-dilutive monetary awards or grants received from external agencies to support product development of the nanoliposome encapsulated BMEDA-chelated radioisotope, which includes grants from CPRIT. As of September 30, 2025, the Company accrued $0.3 million of payments due to NanoTx as a result of the CPRIT Grant proceeds received (see Note 7, Grant Revenue of the condensed consolidated financial statements for additional information).	8. License Agreements UT Health Science Center at San Antonio (“UTHSCSA”) License Agreement On December 31, 2021, the Company entered into a Patent and Know-How License Agreement with UTHSCSA, pursuant to which UTHSCSA granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of biodegradable alginate microspheres containing nanoliposomes loaded with imaging and/or therapeutic payloads. NanoTx License Agreement On March 29, 2020, the Company and NanoTx, Corp. (“NanoTx”) entered into a Patent and Know-How License Agreement (the “NanoTx License Agreement”), pursuant to which NanoTx granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of radiolabeled nanoliposomes. The transaction terms included an upfront payment of $0.4 million in cash and $0.3 million in the Company’s voting stock. The transaction terms also included success-based milestone and royalty payments contingent on key clinical, regulatory and sales milestones, as well as the requirement to pay 15% of any non-dilutive monetary awards or grants received from external agencies to support product development of the nanoliposome encapsulated BMEDA-chelated radioisotope, which includes grants from the Cancer Prevention & Research Institute of Texas (“CPRIT”). As of December 31, 2024, the Company accrued $1.0 million of payments due to NanoTx as a result of the CPRIT grant received (Note 11).

Organization and Operations - Additional Information (Details) - USD ($)		3 Months Ended						9 Months Ended		12 Months Ended
	Mar. 08, 2024	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Aug. 22, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss		$ (4,423,000)	$ 5,151,000	$ (17,401,000)	$ (2,874,000)	$ (2,940,000)	$ (3,261,000)	$ (16,673,000)	$ (9,075,000)	$ (12,978,000)	$ (13,316,000)
Accumulated deficit		(510,152,000)						(510,152,000)		(493,479,000)	(480,501,000)
Cash and cash equivalents		13,289,000						13,289,000		76,000	8,554,000
Net cash used in operating activities								(14,518,000)	$ (9,343,000)	(10,554,000)	(12,851,000)
Outstanding balance										3,292,000
Investments		$ 3,312,000						$ 3,312,000		3,530,000
Stockholders' equity requirement	$ 2,500,000					$ 1,000				$ 1,000	$ 5,005,000
Maintain minimum market value of listed securities	35,000,000											$ 35,000,000
Net income from continuing operations	$ 500,000

Biocept Asset Acquisition - Additional Information (Details) - Biocept Asset Acquisition [Member]	Apr. 26, 2024 USD ($)
Asset Acquisition [Line Items]
Total cash payment	$ 400,000
Costs of acquisitions	$ 45,000

Subsequent Events	9 Months Ended	12 Months Ended
Subsequent Events	Sep. 30, 2025	Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	16. Subsequent Events Financing Related Transactions As of September 30, 2025, the Company recorded a $6.4 million liability in accounts payable and accrued expenses due to the March 2025 Private Placement Purchasers. Such liability declined by $1.3 million from September 30, 2025 to October 27, 2025 due to 1) a $0.9 million reduction as a result of the reselling of securities acquired in the March 2025 Private Placement by certain March 2025 Private Placement Purchasers, which was recorded as a reduction of the liability that would have been settled in cash, with a corresponding increase to stockholders’ equity, and 2) a payment of $0.4 million to the March 2025 Private Placement Purchasers subsequent to September 30, 2025, with 0.6 million shares of the Company’s common stock returned and cancelled under the terms of the Letter Agreement. On October 28, 2025, the Company entered into an amendment to the Letter Agreement and the Support Letters with certain March 2025 Private Placement Purchasers (the “Amendment Agreement”), pursuant to which (a) the Support Letters were terminated other than with respect to the participation rights granted therein, and (b) the repayment mechanism under the Letter Agreement was modified. As modified, the Company is no longer required to use 90% of the proceeds from any subsequent financing to repay the March 2025 Private Placement Purchasers. Instead, the Company is only required to retain sufficient funds in an interest bearing account to cover such repayment obligations and make such repayments upon request by any March 2025 Private Placement Purchaser who executed the Amendment Agreement until each such purchaser has received cash either from the Company or from reselling securities acquired in the March 2025 Private Placement in an amount equal to 115% of the purchase price such purchaser paid in the March 2025 Private Placement. If such requests are made, the requesting purchaser must return shares acquired in the March 2025 Private Placement at a value of $0.66 per share. In addition, the Company issued approximately 3.3 million shares on the Lincoln Park Purchase Credit Agreement, raising an additional $1.9 million of capital through October 29, 2025. Houston Lease On October 16, 2025, the Company entered into a lease (the “Houston Lease”) with LG 1 Property Owner LP, pursuant to which the Company agreed to lease approximately 11,370 rentable square feet of space located at 6420 Levit Green Boulevard, Houston, Texas 77021. The Houston Lease is expected to commence on or about November 1, 2026. The Houston Lease provides for a monthly base rent of $58,745, which increases annually by approximately 3%, plus the Company’s share of the building’s direct expenses. The Houston Lease has an initial term of 120 calendar months.	18. Subsequent Events February 2025 SPEA Agreements On February 13, 2025 (the “Closing Date”), the Company entered into a Securities Purchase and Exchange Agreement (the “February 2025 SPEA”) with certain existing accredited investors (the “Purchasers”). Pursuant to the February 2025 SPEA, on the Closing Date the Company issued secured convertible promissory notes (the “Funding Notes”) in the aggregate principal amount of $3,362,251 together with common stock purchase warrants (the “Warrants”) to purchase 3,002,009 shares of the Company common stock, par value $0.001 (the “Common Stock”) at an exercise price of $1.12 per share (the “Warrant Exercise Price”). The aggregate purchase price for the Funding Notes and Warrants was approximately $3.7 million (the “Aggregate Purchase Price”) and included payment of $0.125 per Warrant. The Funding Notes mature on February 13, 2026, and bear interest at a rate of 10% per annum, subject to increase upon Events of Default. The Warrants are exercisable for five-years from the date of issuance. Secured Interest The obligations of the Company under the February 2025 SPEA and the Notes (as defined below) were secured by a pledge of substantially all of assets of the Company pursuant to a security agreement, dated as of the Closing Date, among the Company, CNSide Diagnostics, LLC (a subsidiary of the Company, “CNSide Diagnostics”), and Iroquois Master Fund Ltd., as collateral agent for the Purchasers (the “Security Agreement), subject to certain exceptions. The Security Agreement contained certain customary affirmative and negative covenants, including limitations on the Company’s and CNSide Diagnostic’s ability to dispose of assets, subject to customary exceptions. The repayment of the Company’s obligations under the February 2025 SPEA and Notes were guaranteed pursuant to a subsidiary guarantee, dated as of the Closing Date (the “Subsidiary Guarantee”), by and among CNSide and the Purchasers. The Security Agreement and the Subsidiary Guarantee were subsequently terminated after the closing of the private placement pursuant to the March 2025 SPA (as defined below). Terms of the February 2025 SPEA The February 2025 SPEA contains certain representations and warranties, covenants and indemnities customary for similar transactions. Under the February 2025 SPEA, the Company agreed, among other conditions, to not effect or enter an agreement to effect any variable rate transaction, except for certain exempt issuances of equity securities, until the later of the two year anniversary of the Closing Date or such date that the Notes are no longer outstanding. The Company also agreed to hold a stockholder meeting by no later than May 30, 2025, to seek approvals for future adjustments of the Warrant Exercise Price and Conversion Price for anti-dilution adjustments and similar matters, the reduction of the exercise price of the Warrants by $0.125, the extension of the period of exercise for the Series B common warrants issued pursuant to the May 2024 Purchase Agreement until five years from the original issue date of those warrants, and other matters necessary for compliance with Nasdaq Listing Rule 5635(d) (the “Stockholder Approvals”). Exchange Notes As previously disclosed in Note 15, the Company entered into that certain securities purchase agreement, dated May 5, 2024, as amended on May 8, 2024 (the “May 2024 Purchase Agreement”), with the Purchasers, among other investors, for the private placement of securities, including Series A common warrants (“Series A Warrants”) to purchase an aggregate of up to 3,591,532 shares of common stock. The May 2024 Purchase Agreement included certain limitations and restrictions on the Company’s ability to issue securities and provided the Purchasers and the other investors signatories to the May 2024 Purchase Agreement participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “Financing Restrictions”). On the Closing Date, pursuant to the February 2025 SPEA, the Company issued to the Purchasers secured convertible promissory notes in the aggregate amount of $ 3,188,922 (the “Exchange Notes” and together with the Funding Notes, the “Notes”) in exchange for cancellation of the Series A Warrants held by the Purchasers, and the Purchasers entered into a second amendment to the May 2024 Purchase Agreement to eliminate the Financing Restrictions. The terms and conditions of the Exchange Notes were substantially identical in all material respects to the Funding Notes, except that the Mandatory Conversion applied to all of the principal amount of the Exchange Notes instead of being limited to seventy- five percent, and the Maximum Amount did not apply. The Security Agreement and Subsidiary Guarantee also applied to the obligations under the Exchange Notes. March 2025 SPEA Agreements On March 4, 2025, the Company entered into a securities purchase agreement (the “March 2025 SPA”) with accredited investors, including certain existing stockholders of the Company, identified on the signature page thereto (collectively, the “March 2025 Private Placement Purchasers”) for a private placement of securities (the “March 2025 Private Placement”). The March 2025 SPA, provides for the sale and issuance by the Company of an aggregate of 28,042,140 shares (the “March 2025 Private Placement Shares”) of the Company’s Common Stock, or, at the election of each Purchaser, prefunded warrants to purchase Common Stock (the “Prefunded Warrants”), exercisable immediately at an exercise price of $0.001 per share (the “Prefunded Warrant Shares”), with each Private Placement Share or Prefunded Warrant accompanied by (i) a Series A common warrant (the “Series A Warrants”) to purchase one share of Common Stock (the “Series A Warrant Shares”), and (ii) one Series B common warrant (the “Series B Warrants”) to purchase one share of Common Stock (the “Series B Warrant Shares,” and together with the Series A Warrant Shares, the “Common Warrant Shares”). The March 2025 Private Placement Shares, Prefunded Warrants, Prefunded Warrant Shares, Series A Warrants, Series B Warrants, and the Common Warrant Shares are collectively referred to herein as the “Securities.” The combined purchase price of $0.66 for each Private Placement Share or $0.659 for each Prefunded Warrant in the Private Placement, together with one accompanying Series A Warrant and one accompanying Series B Warrant, represents the applicable “Minimum Price”. The initial exercise price of each Series A Warrant issued in the Private Placement is $1.32 per share of Common Stock. The Series A Warrants are exercisable only following stockholder approval and expire five (5) years thereafter. The number of securities issuable under the Series A Warrant is subject to adjustment as described in more detail in the Series A Warrant. The Series A Warrant exercise price and the related number of shares of Common Stock issuable upon exercise are subject to a “reset” provision upon certain events and are subject to anti-dilution protection upon any subsequent transaction at a fixed price lower than the warrant exercise price then in effect, as more fully described in the Series A Warrant. The initial exercise price of each Series B Warrant issued in the Private Placement is $1.98 per share of Common Stock or pursuant to an alternative cashless exercise option. The Series B Warrants are exercisable only following stockholder approval and expire two and one-half (2.5) years thereafter. The Series B Warrant exercise price and the related number of shares of Common Stock issuable upon exercise are subject to a “reset” provision upon certain events, as more fully described in the Series A Warrant, and the Series B Warrant alternative cashless exercise provision provides that the Series B Warrant can be exercised without further payment to the Company and for three times the number of shares of Common Stock then subject to the Series B Warrant. The Prefunded Warrants will be exercisable from the date of issuance until exercised in full and may not be exercised to the extent that immediately following such exercise, the holder would beneficially own greater than 4.99% (or, at the election of the holder, greater than 9.99%) of the Company’s outstanding Common Stock. Of the securities issued in the March 2025 Private Placement, 22,727,270 of the shares of Common Stock, or Prefunded Warrants in lieu thereof, and the accompanying 22,727,270 Series A Warrants and 22,727,270 Series B Warrants, were issued in consideration of new capital subscriptions, and 5,314,870 of the shares of Common Stock, or Prefunded Warrants in lieu thereof, and the accompanying 5,314,870 Series A Warrants and 5,314,870 Series B Warrants, were issued in exchange (the “Exchange”) for the cancelation of approximately $ 3.2 million in aggregate principal amount of the Exchange Notes. The March 2025 Private Placement closed on March 7, 2025 (the “Closing Date”). The aggregate gross proceeds at the Closing Date totaled approximately $15.0 million, before deducting certain expenses payable by the Company. In addition to the stockholder approval of the Series A Warrants and Series B Warrants, the Company also covenanted to seek if necessary stockholder approval to, among other things, amend the Company’s Certificate of Incorporation, as amended, to increase the authorized share capital of the Company to an amount sufficient to cover the shares of Common Stock issuable upon the exercise of the Series A Warrants and Series B Warrants. First Amendment to the February 2025 SPEA In connection with entering into the March 2025 SPA, the Company entered into that certain First Amendment to the February 2025 SPEA (the “First Amendment”). The February 2025 SPEA included certain limitations and restrictions on the Company’s ability to issue securities and provided the Investors participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “New Financing Restrictions”). Pursuant to the First Amendment, subject to consummation of the March 2025 Private Placement, the Company agreed to repurchase from the Investors $3,362,251 in principal amount of the Company’s outstanding senior convertible promissory notes (the “Funding Notes”) and 3,002,009 warrants (the “SPEA Warrants”) issued pursuant to the February 2025 SPEA for an aggregate purchase price of $4.25 million. In exchange for the repurchase by the Company of the Funding Notes and SPEA Warrants, the Purchasers agreed to consent to the March 2025 Private Placement and eliminate the New Financing Restrictions.

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($)	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 13,289,000	$ 76,000	$ 8,554,000
Investments	3,312,000	3,530,000
Grant receivable		571,000
Other current assets	985,000	1,082,000	1,280,000
Total current assets	17,586,000	5,259,000	9,834,000
Property and equipment, net	273,000	448,000	906,000
Operating lease right-of-use assets	20,000	73,000	202,000
Goodwill	372,000	372,000	372,000
Intangible assets, net	374,000	469,000	42,000
Other assets	45,000	12,000	32,000
Total assets	18,670,000	6,633,000	11,388,000
Current liabilities:
Accounts payable and accrued expenses	11,623,000	11,288,000	6,631,000
Operating lease liability	21,000	44,000	120,000
Deferred grant liability	1,972,000	927,000
Line of credit		3,292,000
Term loan obligation, current			3,976,000
Total current liabilities	13,616,000	15,551,000	10,727,000
Noncurrent operating lease liability		31,000	85,000
Deferred grant liability			1,924,000
Total liabilities	13,616,000	15,582,000	12,736,000
Commitments and contingencies (Note 8)
Stockholders' equity (deficit):
Preferred stock, $0.001 par value; 5,000,000 shares authorized; 1,952 shares issued and outstanding as of September 30, 2025 and December 31, 2024, respectively
Common stock, $0.001 par value; 2,000,000,000 shares authorized; 131,863,969 shares issued; and 131,605,544 shares outstanding as of September 30, 2025, and 100,000,00 shares authorized; 6,154,758 shares issued; and 5,896,333 shares outstanding as of December 31, 2024, respectively	132,000	6,000	5,000
Treasury stock (at cost), 258,425 shares as of September 30, 2025 and December 31, 2024, respectively	(500,000)	(500,000)	(126,000)
Additional paid-in capital	515,574,000	485,024,000	479,274,000
Accumulated deficit	(510,152,000)	(493,479,000)	(480,501,000)
Total stockholders' equity (deficit)	5,054,000	(8,949,000)	(1,348,000)
Total liabilities and stockholders' equity	$ 18,670,000	$ 6,633,000	$ 11,388,000

Composition of Certain Financial Statement Captions - Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Accounts Payable and Accrued Expenses [Abstract]
Accounts payable		$ 9,474	$ 4,758
Accrued payroll and bonus		920	987
Accrued professional fees		236	128
Accrued vacation and compensation		356	370
Accrued R&D studies		185	388
Accrued interest		117
Accounts payable and accrued expenses, Total	$ 11,623	$ 11,288	$ 6,631

Composition of Certain Financial Statement Captions - Intangible Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 767	$ 221
Accumulated Amortization	(298)	(179)
Intangible Asset, Net	469	42
Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	221	221
Accumulated Amortization	(218)	(179)
Intangible Asset, Net	3	$ 42
Intellectual Property [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	546
Accumulated Amortization	(80)
Intangible Asset, Net	$ 466

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Fair Value Measurements - Schedule of Change in Fair Value of Warrant Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance as of January 1, 2025	$ 0	$ 0
Issuance of warrants	16,010	10,854
Change in fair value of warrants	3,147	(5,654)
Reclassification to equity		(5,200)
Ending balance as of September 30, 2025	$ 0	$ 0

Segment Information - Additional Information (Details) - SEGMENT	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting [Abstract]
Number of operating segment	1	1	1
Segment Reporting, Expense Information Used by CODM, Description	The determination of a single reportable business segment is consistent with the consolidated financial information regularly provided to the Company’s CODM. All of the Company’s long-term assets and operations are located in the United States, and the measure of segment assets is reported on the condensed consolidated balance sheets as total assets.	The determination of a single reportable business segment is consistent with the consolidated financial information regularly provided to the Company’s CODM. All of the Company’s long-term assets and operations are located in the United States.
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	Chief Executive Officer [Member]	Chief Executive Officer [Member]
Segment Reporting, Expense Information Used by CODM, Type [Extensible Enumeration]	Net Income (Loss) Attributable to Parent	Net Income (Loss) Attributable to Parent

Income Taxes - Reconciliation of Total Income Tax Provision (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Reconciliation of the total income tax provision tax rate [Abstract]
Income tax expense (benefit) at federal statutory rate	(21.00%)	(21.00%)
Change in valuation allowance	23.80%	25.50%
Income tax benefit at state statutory rate	(0.30%)	(0.20%)
Share-based compensation	0.90%	1.00%
Warrants	(2.60%)	0.00%
NOLs expiring and adjustments to NOL	(0.10%)	(0.10%)
Research credit	(0.70%)	(5.10%)
Return to provision	0.00%	(0.10%)
Total income tax provision	0.00%	0.00%

Loss per Share (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Earnings Per Share [Abstract]

Schedule of Computation of Basic and Diluted Net Loss Per Share of Common Stock

The following table sets forth the computation of basic and diluted net loss per share of common stock for the periods indicated, in thousands except share and per share data:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2025			2024			2025			2024
Basic and diluted net loss per common share calculation:
Net loss	$	(4,423	)	$	(2,874	)	$	(16,673	)	$	(9,075	)
Change in fair value of derivative instruments		—			—			—			(5,047	)

Net loss attributable to common stockholders – basic		(4,423	)		(2,874	)		(16,673	)		(14,122	)
Weighted average common stock outstanding – basic		107,428,969			7,855,763			57,845,406			6,232,123
Net loss per share of common stock – basic	$	(0.04	)	$	(0.37	)	$	(0.29	)	$	(1.46	)
Weighted average common stock outstanding – diluted		107,428,969			7,855,763			57,845,406			8,452,338
Net loss per share of common stock – diluted	$	(0.04	)	$	(0.37	)	$	(0.29	)	$	(1.67	)

The following table sets forth the computation of basic and diluted net loss per share of common stock for the periods indicated, in thousands except share and per share data:


	For the Year Ended December 31,
	2024			2023
Basic and diluted net loss per share of common stock calculation:
Net loss	$	(12,978	)	$	(13,316	)
Change in fair value of warrants		(5,047	)		—

Net loss attributable to common stockholders - diluted	$	(18,025	)	$	(13,316	)

Weighted average shares of common stock outstanding - basic		6,640,251			3,140,925
Net loss per share of common stock - basic	$	(1.95	)	$	(4.24	)
Weighted average shares of common stock - diluted		7,700,774			3,140,925
Net loss per share of common stock - diluted	$	(2.34	)	$	(4.24	)

Schedule of Antidilutive Securities Excluded from Diluted Loss per Share


	As of September 30,
	2025		2024
Outstanding stock options		11,272,863		598,540
Outstanding restricted stock units		2,823,857		—
Preferred stock		28,190		28,190
Outstanding warrants (Note 13)		3,141,993		706,674

Total		17,266,903		1,333,404

The following were excluded from the diluted loss per share calculation for the periods presented because their effect would be anti-dilutive:


	For the Year Ended December 31,
	2024		2023
Outstanding stock options		598,540		140,109
Preferred stock		28,190		28,190
Outstanding warrants		7,183,064		142,733

Total		7,809,794		311,032

Share-Based Compensation - Weighted-average Assumptions (Details) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Black-Scholes-Merton option valuation model based on weighted-average assumptions [Abstract]
Expected term	6 years	6 years
Risk-free interest rate	3.79%	4.06%
Expected volatility	120.60%	127.00%
Dividends	0.00%	0.00%
Resulting fair value	$ 1.39	$ 4.47

Grant Revenue - Additional Information (Details) - USD ($)			1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 01, 2024	Sep. 19, 2022	Feb. 28, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Oct. 04, 2024
Disaggregation of Revenue [Line Items]
Revenue recognized				$ 1,397,000	$ 1,456,000	$ 3,846,000	$ 4,412,000	$ 5,824,000	$ 4,913,000
CPRIT Contract [Member]
Disaggregation of Revenue [Line Items]
Grant funding term		3 years
CPRIT grant funding term, description						The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQ based on specific dollar thresholds and tiered low single digit royalty rates until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements.		The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQ™ based on specific dollar thresholds and tiered low single digit royalty rates until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements.
Contract effective date		Aug. 31, 2022
Contract termination date		Aug. 30, 2025
Percentage of aggregate amount of proceeds awarded under CPRIT grant		400.00%
Percentage of grant proceeds with interest not exceed annually		5.00%
CPRIT Contract [Member] \| Grant [Member]
Disaggregation of Revenue [Line Items]
Revenue recognized			$ 2,000,000	1,400,000	$ 3,800,000	$ 1,500,000	$ 4,400,000	$ 5,800,000	4,900,000
Grant revenue receivable				0		0		600,000
Deferred grant liability				$ 1,100,000		1,100,000		0	$ 1,900,000
Congressionally Directed Medical Research Programs [Member]
Disaggregation of Revenue [Line Items]
Amount to be received as award for research and development	$ 3,000,000
Department of Defense Award [Member]
Disaggregation of Revenue [Line Items]
Research and development award in period	3 years
Grant revenue						$ 0		$ 0
First payment received										$ 900,000

Stock-Based Compensation - Summary of Restricted Stock Units Activity (Details) - Restricted Stock Unit [Member]	9 Months Ended
	Sep. 30, 2025 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested as of December 31, 2024 \| shares	0
Granted \| shares	2,823,857
Unvested as of September 30, 2025 \| shares	2,823,857
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Unvested as of December 31, 2024 \| $ / shares	$ 0
Granted \| $ / shares	0.57
Unvested as of September 30, 2025 \| $ / shares	$ 0.57

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) - Recurring Basis [Member] - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		$ 74
Investments	$ 3,312	3,530
Money Market [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	15	74
Investments		696
Fair Value			$ 5,449
Treasury Bills and Treasury Note[Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,309	2,062
Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,003	772
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		74
Investments	1,003	1,468
Level 1 [Member] \| Money Market [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	15	74
Investments		696
Fair Value			$ 5,449
Level 1 [Member] \| Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,003	772
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,309	2,062
Level 2 [Member] \| Treasury Bills and Treasury Note[Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 2,309	$ 2,062

Stockholders' Equity - Preferred Stock (Details)		9 Months Ended	12 Months Ended
Stockholders' Equity - Preferred Stock (Details)	Mar. 03, 2023 USD ($) Votes $ / shares shares	Sep. 30, 2025 $ / shares shares	Dec. 31, 2024 $ / shares shares	Dec. 31, 2023 shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)		5,000,000	5,000,000	5,000,000
Preferred stock, par value (in dollars per share) \| $ / shares		$ 0.001	$ 0.001
Preferred stock, shares outstanding (in shares)		1,952	1,952
Series F Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1
Number Of Votes Per Share \| Votes	50,000,000
Consideration paid to preferred stock holders \| $	$ 1,000
Series F Convertible Preferred Stock [Member] \| Subscription Agreement [Member]
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.001
Stock Issued During Period, Shares, New Issues	1
Consideration to purchaser in cash \| $	$ 1,000
Sale closed date	Mar. 03, 2023
Series B Convertible Preferred Stock [Member] \| 2018 Rights Offering [Member]
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)		1,014	1,014
Number of preferred stock, shares converted		398	398
Series C Convertible Preferred Stock [Member] \| 2018 Rights Offering [Member]
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)		938	938
Number of preferred stock, shares converted		27,792	27,792

Short-Term Investments

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

Short-Term Investments

The Company classified short-term investments as

available-for-sale

securities, as the sale of such investments may be required prior to maturity to facilitate the execution of management strategies. During the three and nine months ended September 30, 2025, the unrealized gain on the Company’s

available-for-sale

securities was immaterial, and not presented separately in the condensed consolidated statements of operations.

The Company classified all investments with maturities longer than three months from the date of purchase as short-term investments in the condensed consolidated balance sheets, reflecting its intent and ability to use these assets to meet the liquidity requirements of current operations. The following table summarizes contractual maturities of

available-for-sale

securities as of September 30, 2025 (in thousands):


	Amortized Cost		Estimated Fair Value
Due in one year or less	$	2,309	$	2,309
Due after one year through five years		—		—
Due after five years		1,003		1,003

Total Investments	$	3,312	$	3,312

Liquidity and Going Concern - Additional Information (Details) - USD ($)						3 Months Ended						9 Months Ended		12 Months Ended
	Nov. 12, 2025	Aug. 22, 2025	Jul. 22, 2025	May 16, 2025	Mar. 08, 2024	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income loss						$ (4,423,000)	$ 5,151,000	$ (17,401,000)	$ (2,874,000)	$ (2,940,000)	$ (3,261,000)	$ (16,673,000)	$ (9,075,000)	$ (12,978,000)	$ (13,316,000)
Accumulated deficit						(510,152,000)						(510,152,000)		(493,479,000)	(480,501,000)
Net cash used in operating activities												(14,518,000)	(9,343,000)	(10,554,000)	(12,851,000)
Stockholders' deficit						$ 5,054,000	$ 3,034,000	$ (23,641,000)	$ (5,174,000)	(7,625,000)	$ (4,837,000)	$ 5,054,000	$ (5,174,000)	(8,949,000)	(1,348,000)	$ 6,445,000
Stockholders' equity requirement					$ 2,500,000					$ 1,000				$ 1,000	$ 5,005,000
Net income from continuing operations					500,000
Maintain minimum market value of listed securities		$ 35,000,000			$ 35,000,000
Consecutive business days				30 days
Period for regain compliance				180 days
Regain compliance expiry date				Nov. 12, 2025
Minimum stockholder's equity requirement date			Aug. 14, 2025
Minimum bid requirement date			Sep. 08, 2025
Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Additional period for regain compliance on achievement of compliance	180 days
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reverse stock split												one-for-two hundred fifty
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Closing bid price for common stock had fallen below		$ 1		$ 1
Reverse stock split												one-for twenty five
Minimum [Member] \| Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Closing bid price for common stock had fallen below	$ 1
Consecutive business days	10 years

Composition of Certain Financial Statement Captions - Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid services	$ 551	$ 87	$ 410
Deferred costs (Note 8)	299	436	234
Prepaid insurance	135	559	636
Total other current assets	$ 985	$ 1,082	$ 1,280

Stockholders' Equity - Common stock (Details)																	3 Months Ended		4 Months Ended		9 Months Ended		12 Months Ended		28 Months Ended
Stockholders' Equity - Common stock (Details)	Aug. 14, 2025 shares	Jul. 11, 2025 USD ($)	Jul. 10, 2025	Jun. 23, 2025 USD ($) BusinessDay $ / shares shares	Jun. 18, 2025 shares	Jun. 17, 2025 USD ($) $ / shares shares	May 02, 2025 USD ($) shares	Mar. 07, 2025 USD ($)	Mar. 04, 2025 USD ($) $ / shares shares	Feb. 13, 2025 USD ($) $ / shares shares	Aug. 09, 2024 USD ($)	May 09, 2024 USD ($) shares	May 08, 2024 USD ($) shares	May 05, 2024 USD ($) $ / shares shares	Aug. 02, 2022 USD ($) shares	May 16, 2022 shares	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($) shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Jun. 30, 2025 USD ($)	Jun. 16, 2025	May 19, 2025 $ / shares	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Oct. 31, 2023 USD ($)	Aug. 18, 2023 shares	Aug. 17, 2022 shares	Jul. 14, 2022 shares
Class of Stock [Line Items]
Financing expense																							$ 3,545,000
Change in fair value of warrants																					$ 800,000		$ (5,654,000)
Common stock, shares authorized (in shares) \| shares																			100,000,000		2,000,000,000		100,000,000	100,000,000	100,000,000
Proceeds from sale of common stock, net																					$ 19,612,000
Remained authorized amount for repurchase																							$ 0		$ 0
Common stock, par value (in dollars per share) \| $ / shares																			$ 0.001		$ 0.001		$ 0.001	$ 0.001	$ 0.001
Class of warrant outstanding \| shares																					5,753,802
Fair value																			$ 0		$ 0		$ 0	$ 0	$ 0
Excess of fair value of instruments issued over cash received																					1,389,000
Change in fair value of derivative instruments																	$ (960,000)				2,631,000	$ (5,654,000)
Stockholders' deficit																	(5,174,000)	$ (7,625,000)	(1,348,000)	$ 6,445,000	$ 5,054,000	(5,174,000)	$ (8,949,000)	$ (1,348,000)	(8,949,000)	$ 3,034,000			$ (23,641,000)	$ (4,837,000)
Number of shares issuable upon exercise \| shares																					1
Series A Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares																												$ 0.4373
Series A Warrant and Series B Warrant [Member] \| Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Fair value of warrant liability reclassified to equity											$ 5,200,000
Common Stock [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares																		1,439,988					1,439,988	2,230,493
Number of stock repurchased \| shares																							179,866	78,559
Treasury stock																			100,000				$ 400,000	$ 100,000	400,000
Stockholders' deficit																	$ 6,000	$ 6,000	$ 5,000	$ 2,000	$ 132,000	$ 6,000	6,000	$ 5,000	$ 6,000	$ 92,000			17,000	$ 5,000
Common Stock [Member] \| Maximum [Member]
Class of Stock [Line Items]
Authorized amount of repurchase of stock																															$ 500,000
Common Stock [Member] \| Series A Warrant [Member] \| Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Restricted beneficial ownership level result of exercise of warrant to receive pre-funded warrant														4.99%
Common Stock [Member] \| Series B Warrant [Member]
Class of Stock [Line Items]
Number of shares issued \| shares							21,482,492
Common Stock [Member] \| Series B Warrant [Member] \| Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Restricted beneficial ownership level result of exercise of warrant to receive pre-funded warrant														9.99%
Lincoln Park Capital Fund, LLC [Member] \| Letter Agreement [Member]
Class of Stock [Line Items]
Potential cash payment		$ 500,000																			2,300,000
Modification period		30 days
Potential financing percentage		50.00%	90.00%
Support letter participation rights period		12 months
Financing percentage after modification period		90.00%
Lincoln Park Capital Fund, LLC [Member] \| Minimum [Member] \| Letter Agreement [Member]
Class of Stock [Line Items]
Stockholders' deficit		$ 3,000,000
May 2024 Private Placement
Class of Stock [Line Items]
Financing expense														$ 3,500,000
Change in fair value of warrants																							$ 5,700,000
May 2024 Private Placement \| Common Stock [Member]
Class of Stock [Line Items]
Number of shares issued \| shares												1,439,988
Proceeds from private placement												$ 7,300,000
Offering expenses												$ 400,000
Proceeds from issuance of warrants														$ 10,900,000
May 2024 Private Placement \| Common Stock [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares														3,591,532
Warrant exercise price (in dollars per share) \| $ / shares														$ 0.001
May 2024 Private Placement \| Common Stock [Member] \| Initial Subscription [Member] \| Private Placement And Prefunded Warrant [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares														2.022
May 2024 Private Placement \| Common Stock [Member] \| Additional Subscription [Member] \| Private Placement And Prefunded Warrant [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares														$ 2.158
May 2024 Private Placement \| Common Stock [Member] \| Series A Warrant [Member]
Class of Stock [Line Items]
Number of shares issued \| shares												3,591,532		3,591,532
May 2024 Private Placement \| Common Stock [Member] \| Series A Warrant [Member] \| Initial Subscription [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares														$ 1.772
May 2024 Private Placement \| Common Stock [Member] \| Series B Warrant [Member]
Class of Stock [Line Items]
Number of shares issued \| shares												3,591,532		3,591,532
May 2024 Private Placement \| Common Stock [Member] \| Series B Warrant [Member] \| Additional Subscription [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares														$ 1.908
May 2024 Private Placement \| Common Stock [Member] \| Series A Warrant and Series B Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares														1.79
May 2024 Private Placement \| Common Stock [Member] \| Series A Warrant and Series B Warrant [Member] \| Initial Subscription [Member]
Class of Stock [Line Items]
Closing price per share \| $ / shares														$ 2.04
May 2024 Private Placement \| Common Stock [Member] \| Pre-Funded Warrants [Member]
Class of Stock [Line Items]
Number of shares issued \| shares												2,151,544
Number of securities called by warrant or right \| shares																							1,959,430		1,959,430
2022 Purchase Agreement [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares																							0
2022 Purchase Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member] \| Maximum [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares) \| shares																57,500,000
2022 Purchase Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Maximum value of shares to be issued under agreement															$ 50,000,000
Issue and sale of share \| shares																			150,000	266,666				410,500
Period exercisable from the date of issuance																							36 months
Number of maximum common shares can be resale \| shares																																	633,333
Initial commitment shares \| shares															32,846																			32,846
Initial commitment fee paid in cash															$ 100,000
Aggregate gross proceeds from sales of common stock															$ 25,000,000
Proceeds from sale of common stock, net																				$ 3,200,000				$ 1,000,000
2022 Purchase Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member] \| Minimum [Member]
Class of Stock [Line Items]
Percentage issuance of common stock																19.99%
2022 Purchase Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member] \| Maximum [Member]
Class of Stock [Line Items]
Number of maximum common shares can be resale \| shares																																1,500,000
Number of shares reserved for issuance and sale \| shares																																	600,486
2020 Purchase Agreement [Member] \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares																									527,166
February 2025 SPEA Agreements
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares										$ 1.12
Purchase price of share \| $ / shares										$ 0.125
Proceeds from private placement										$ 4,200,000
Common stock, par value (in dollars per share) \| $ / shares										$ 0.001
Aggregate purchase price										$ 3,700,000
Maturity date										Feb. 13, 2026
Interest rate										10.00%
February 2025 SPEA Agreements \| SPEA Warrants [Member]
Class of Stock [Line Items]
Aggregate purchase price										$ 4,200,000
February 2025 SPEA Agreements \| February 2025 Warrants [Member]
Class of Stock [Line Items]
Fair value										$ 500,000
Change in fair value of derivative instruments																					2,200,000
February 2025 SPEA Agreements \| Common Stock [Member]
Class of Stock [Line Items]
Number of securities called by warrant or right \| shares										3,002,009
Aggregate principal amount										$ 3,300,000
May 2024 Purchase Agreement
Class of Stock [Line Items]
Financing expense																					3,100,000
Aggregate principal amount										3,200,000			$ 3,188,922
May 2024 Purchase Agreement \| Exchange Notes
Class of Stock [Line Items]
Fair value										3,800,000
Change in fair value of derivative instruments																					300,000
May 2024 Purchase Agreement \| Funding Notes
Class of Stock [Line Items]
Fair value										4,000,000
Change in fair value of derivative instruments																					300,000
May 2024 Purchase Agreement \| Series A Warrant [Member]
Class of Stock [Line Items]
Fair value										2,700,000
Excess of fair value of instruments issued over cash received																					3,700,000
Carrying value of warrants exchanged																					$ 3,700,000
May 2024 Purchase Agreement \| Common Stock [Member] \| Series A Warrant [Member]
Class of Stock [Line Items]
Number of shares issued \| shares													3,591,532
March 2025 Private Placement
Class of Stock [Line Items]
Offering expenses								$ 1,400,000
Fair value of warrant liability reclassified to equity								5,800,000
Aggregate principal amount										$ 3,400,000
Warrant issuance expenses								1,000,000
Fair value								13,200,000
Percentage agreed to repay purchasers holding securities						115.00%
Percentage of proceeds to repay purchasers from capital raised						90.00%
March 2025 Private Placement \| Private Placement And Prefunded Warrant [Member]
Class of Stock [Line Items]
Number of shares agreed to return \| shares						12,241,986
March 2025 Private Placement \| Private Placement Share [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares						$ 0.66
Shares returned and cancelled \| shares																					3,472,740
Paid purchasers to returened shares																					$ 2,300,000
March 2025 Private Placement \| Prefunded Warrant [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares						$ 0.659
Number of securities called by warrant or right \| shares						10,633,650
March 2025 Private Placement \| Exchange Notes
Class of Stock [Line Items]
Fair value									$ 3,500,000
March 2025 Private Placement \| Exchange [Member]
Class of Stock [Line Items]
Aggregate principal amount									$ 3,200,000
March 2025 Private Placement \| Series A Warrant [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									28,042,138
March 2025 Private Placement \| Series A Warrant [Member] \| New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									22,727,270
March 2025 Private Placement \| Series A Warrant [Member] \| Exchange [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									5,314,870
March 2025 Private Placement \| Series B Warrant [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									28,042,138
March 2025 Private Placement \| Series B Warrant [Member] \| New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									22,727,270
March 2025 Private Placement \| Series B Warrant [Member] \| Exchange [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									5,314,870
March 2025 Private Placement \| Series A Warrant and Series B Warrant [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Class of warrant outstanding \| shares																					2,611,809
March 2025 Private Placement \| Pre-Funded Warrants [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									23,972,400
March 2025 Private Placement \| Pre-Funded Warrants [Member] \| New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									19,650,000
March 2025 Private Placement \| Pre-Funded Warrants [Member] \| Exchange [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									4,322,400
March 2025 Private Placement \| Common Stock [Member]
Class of Stock [Line Items]
Proceeds from private placement								15,000,000
Offering expenses								$ 400,000
Maximum beneficial ownership percentage									4.99%
Maximum beneficial ownership percentage by election of holder									9.99%
March 2025 Private Placement \| Common Stock [Member] \| Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares									28,042,140
Warrant exercise price (in dollars per share) \| $ / shares									$ 0.001
Number of shares issued \| shares									4,069,738
March 2025 Private Placement \| Common Stock [Member] \| Private Placement Share [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares									$ 0.66
March 2025 Private Placement \| Common Stock [Member] \| Prefunded Warrant [Member]
Class of Stock [Line Items]
Purchase price of share \| $ / shares									$ 0.659
March 2025 Private Placement \| Common Stock [Member] \| New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									3,077,270
March 2025 Private Placement \| Common Stock [Member] \| Exchange [Member]
Class of Stock [Line Items]
Number of shares issued \| shares									992,468
March 2025 Private Placement \| Common Stock [Member] \| Series A Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares									$ 1.32
Number of shares issued \| shares												3,591,532		3,591,532
Floor price \| $ / shares									$ 0.132
Expiration period									5 years
March 2025 Private Placement \| Common Stock [Member] \| Series B Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares									$ 1.98
Number of shares issued \| shares												3,591,532		3,591,532
Expiration period									2 years 6 months
March 2025 Private Placement \| Common Stock [Member] \| Pre-Funded Warrants [Member]
Class of Stock [Line Items]
Number of shares issued \| shares												2,151,544
March 2025 Series A Warrants
Class of Stock [Line Items]
Change in fair value of warrants																					$ 2,700,000
Fair value																													$ 5,000,000
Extinguishment of Warrants																					2,300,000
March 2025 Series B Warrants [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) \| $ / shares						$ 1.98
Change in fair value of warrants							$ 3,800,000
Number of securities called by warrant or right \| shares					34,794,540	35,536,380
Fair value of warrant liability reclassified to equity						$ 11,000,000
Remeasurement of warrant liability						$ 4,500,000
Cashless warrants excercised for common stock \| shares					34,794,540
Warrants exercise ratio						1																					3
Lincoln Park Purchase Agreement \| Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Common stock, par value (in dollars per share) \| $ / shares						$ 0.001
Maximum obligation under single regular purchase				$ 1,000,000
Legal fees																					$ 50,000
Lincoln Park Purchase Agreement \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Maximum value of shares to be issued under agreement						$ 50,000,000
Issue and sale of share \| shares	1,612,903																				44,575,496
Period exercisable from the date of issuance																					36 months
Number of maximum common shares can be resale \| shares																					50,000,000
Initial commitment fee paid in cash						500,000
Aggregate gross proceeds from sales of common stock						25,000,000															$ 19,600,000
Additional commitment fee paid in cash						$ 500,000
Regular purchase price per share threshold percentage				97.00%
Consecutive business days \| BusinessDay				10
Accelerated purchase price per share threshold percentage				96.50%
Additional accelerated purchase price per share threshold percentage				96.50%
Lincoln Park Purchase Agreement \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member] \| Closing Stock Price Not Below $0.10 [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares				300,000
Closing price per share \| $ / shares				$ 0.1
Lincoln Park Purchase Agreement \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member] \| Closing Stock Price Not Below $0.50 [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares				400,000
Closing price per share \| $ / shares				$ 0.5
Lincoln Park Purchase Agreement \| Lincoln Park Capital Fund, LLC [Member] \| Common Stock [Member] \| Closing Stock Price Not Below $0.75 [Member]
Class of Stock [Line Items]
Issue and sale of share \| shares				500,000
Closing price per share \| $ / shares				$ 0.75

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets [Abstract]
Accrued expenses	$ 249	$ 269
Share based compensation	94	99
Net operating loss carryforwards	15,412	13,397
Income tax credit carryforwards	1,725	1,630
Property and equipment, net	218	154
Intangible assets	730	685
Capitalized R&D	3,949	2,842
Other, net	213	453
Total deferred tax assets	22,590	19,529
Valuation allowance	(22,575)	(19,486)
Total deferred tax assets, net of allowance	15	43
Deferred tax liabilities [Abstract]
Other	(15)	(43)
Total deferred tax liability	(15)	(43)
Net deferred tax assets (liability)	$ 0	$ 0

Cover Page	9 Months Ended
Cover Page	Sep. 30, 2025
Document Information [Line Items]
Document Type	S-1
Amendment Flag	false
Entity Registrant Name	PLUS THERAPEUTICS, INC.
Entity Central Index Key	0001095981
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	33-0827593
Entity Address, Address Line One	6420 Levit Green Boulevard
Entity Address, Address Line Two	Suite 310
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77021
City Area Code	737
Local Phone Number	255-7194
Entity Primary SIC Number	2834
Business Contact [Member]
Document Information [Line Items]
Entity Address, Address Line One	6420 Levit Green Boulevard
Entity Address, Address Line Two	Suite 310
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77021
City Area Code	737
Local Phone Number	255-7194
Contact Personnel Name	Andrew Sims

Stock-Based Compensation

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

14. Stock-Based Compensation

Under the Company’s 2015 New Employee Incentive Plan (the “2015 Plan”), awards may only be granted to employees who were not previously an employee or director of the Company, or following a bona fide period of

non-employment,

as a material inducement to entering into employment with the Company. As of September 30, 2025, there were 76,025 shares of common stock remaining and available for future issuances under the 2015 Plan.

The Company’s 2020 Stock Incentive Plan (the “2020 Plan”), which replaced the Company’s 2014 Equity Incentive Plan, provides for the award or sale of shares of common stock (including restricted stock), the award of stock units and stock appreciation rights, and the grant of both incentive stock options to purchase common stock to directors, officers, employees and consultants of the Company. During the three months ended September 30, 2025, there was an additional 20,000,000 shares approved to be issued under the 2020 Plan. The 2020 Plan, as amended, provides for the issuance of up to 21,303,334 shares of common stock, plus the number of shares available for issuance is increased to the extent that awards granted under the 2020 Plan and the Company’s 2014 Equity Incentive Plan are forfeited or expire (except as otherwise provided in the 2020 Plan). As of September 30, 2025, there were 10,005,151 shares remaining and available for future issuances under the 2020 Plan.

Generally, options issued under the 2020 Plan are subject to a

two-year

or four-year vesting schedule with 25% of the options vesting on the one year anniversary of the grant date followed by equal monthly installment vesting, and have a contractual term of 10 years.

A summary of stock option activity for the nine months ended September 30, 2025 is as follows:


	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2024		598,540		$	7.08		9.00	$	—
Granted		10,800,137		$	0.61		—	$	—
Cancelled/forfeited/expired		(125,814	)	$	4.50		—	$	—

Outstanding as of September 30, 2025		11,272,863		$	0.91		9.76	$	1,103

Vested and expected to vest at September 30, 2025		10,073,271		$	0.94		9.75	$	980
Exercisable at September 30, 2025		692,781		$	5.15		8.99	$	33

As of September 30, 2025, the total compensation cost related to

non-vested

stock options not yet recognized for all the Company’s plans is approximately $5.4 million, which is expected to be recognized as a result of vesting under service conditions over a weighted average period of 3.29 years.

Generally, restricted stock units represent the right to receive a certain number of shares of common stock subject to certain vesting conditions and other restrictions. The fair value of restricted stock units is determined by the closing market price on the grant date.

A summary of restricted stock unit activity for the nine months ended September 30, 2025 is as follows:


	Shares		Weighted Average Grant Date Fair Value
Unvested as of December 31, 2024		—	$	—
Granted		2,823,857	$	0.57
Vested		—	$	—
Cancelled/forfeited		—	$	—

Unvested as of September 30, 2025		2,823,857	$	0.57

Restricted stock units granted during the nine months ended September 30, 2025 generally vest over a

36-month

period upon satisfaction of service conditions. As of September 30, 2025, the total compensation cost related to

non-vested

restricted stock units not yet recognized for all the Company’s plans is approximately $1.5 million, which is expected to be recognized as a result of vesting under service

conditions

over a weighted average period of 2.75 years.

16. Share-based Compensation

non-employment,

as a material inducement to entering into employment with the Company. As of December 31, 2024, there were 62,908 shares of common stock remaining and available for future issuances under the 2015 Plan.

The Company’s 2020 Stock Incentive Plan (the “2020 Plan”), which replaced the Company’s 2014 Equity Incentive Plan, provides for the award or sale of shares of common stock (including restricted stock), the award of stock units and stock appreciation rights, and the grant of both incentive stock options to purchase common stock to directors, officers, employees and consultants of the Company. The 2020 Plan, as amended, provides for the issuance of up to 3,550,000 shares of common stock, plus the number of shares available for issuance is increased to the extent that awards granted under the 2020 Plan and the Company’s 2014 Equity Incentive Plan are forfeited or expire (except as otherwise provided in the 2020 Plan). As of December 31, 2024, there were 692,596 shares remaining and available for future issuances under the 2020 Plan.

Generally, options issued under the 2020 Plan are subject to a

two-year

or four-year vesting schedule with 25% of the options vesting on the one year anniversary of the grant date followed by equal monthly installment vesting, and have a contractual term of 10 years.

A summary of activity for the year ended December 31, 2024 is as follows:


	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Balance as of December 31, 2023		140,109		$	37.48		8.07
Granted		506,127			1.58
Cancelled/forfeited		(47,696	)		38.02

Balance as of December 31, 2024		598,540		$	7.08		9.00	$	—

Vested and expected to vest at December 31, 2024		547,893		$	7.52		9.00	$	—

Exercisable at December 31, 2024		144,739		$	22.96		7.60	$	—

The Company settles exercises of stock options with newly issued shares of its common stock. There were no stock options exercised in 2024 or 2023.

The estimated fair value of options, including the effect of estimated forfeitures, is recognized over the requisite service period, which is typically the vesting period of each option. The fair value of each option awarded during the years ended December 31, 2024 and 2023 was estimated on the date of grant using the Black-Scholes-Merton option valuation model based on the following weighted-average assumptions:


	December 31, 2024			December 31, 2023
Expected term		6.0 years			6.0 years
Risk-free interest rate		3.79	%		4.06	%
Expected volatility		120.6	%		127.0	%
Dividends		0	%		0	%
Resulting fair value	$	1.39		$	4.47

The weighted average risk-free interest rate represents the interest rate for treasury constant maturity instruments published by the Federal Reserve Board. If the term of available treasury constant maturity instruments is not equal to the expected term of an employee option, the Company uses the weighted average of the two Federal Reserve securities closest to the expected term of the employee option.

The dividend yield has been assumed to be zero as the Company (a) has never declared or paid any dividends and (b) does not currently anticipate paying any cash dividends on its outstanding shares of common stock in the foreseeable future.

The following table summarizes share-based compensation recognized during the years ended December 31, 2024 and 2023 in the statement of operations (in thousands):


	Years ended December 31,
	2024		2023
Research and development	$	51	$	66
General and administrative		499		503

Total share-based compensation	$	550	$	569

As of December 31, 2024, the total compensation cost related to

non-vested

stock options and stock awards not yet recognized for all our plans is approximately $0.7 million, which is expected to be recognized as a result of vesting under service conditions over a weighted average period of 2.8 years.

Segment Information - Schedule of Segment Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Total research and development	$ 2,436	$ 2,858	$ 5,438	$ 8,394	$ 10,580	$ 9,690
Total general and administrative	3,443	2,397	7,964	6,813	9,939	8,544
Clinical Development and Licensing Expenses [Member]
Segment Reporting Information [Line Items]
Total research and development	1,362	873	2,698	3,548	4,549	5,062
Personnel Related Expenses [Member]
Segment Reporting Information [Line Items]
Total research and development	434	806	1,316	2,435	3,026	2,852
Total general and administrative	1,309	705	3,256	2,052	3,454	3,006
Professional Fees [Member]
Segment Reporting Information [Line Items]
Total research and development	391	830	737	1,412	1,733	635
Total general and administrative	1,744	1,281	3,748	3,585	4,828	3,870
Facility And Other Overhead Expenses [Member]
Segment Reporting Information [Line Items]
Total research and development	249	349	687	999	1,272	1,141
Total general and administrative	$ 390	$ 411	$ 960	$ 1,176	$ 1,657	$ 1,668

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Summary of Lease Costs

The table below summarizes the Company’s operating lease costs from its statements of operations, and cash payments from its statements of cash flows (in thousands).


	Year Ended December 31,
	2024		2023
Lease expense:
Operating lease expense	$	145	$	141

Total lease expense	$	145	$	141

Cash payment information:
Operating cash used for operating leases	$	180	$	141

Total cash paid for amounts included in the measurement of lease liabilities	$	180	$	141

Summary of Future Minimum Annual Lease Payments under Operating Leases

The Company’s future minimum annual lease payments under operating leases at December 31, 2024 are as follows (in thousands):


	Operating Leases
2025	$	69
2026		11

Total minimum lease payments		80

Less: amount representing interest	$	(5	)

Present value of obligations under leases		75

Less: current portion		44

Noncurrent lease obligations	$	31

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - $ / shares	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Stockholders' equity (deficit):
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	1,952	1,952
Preferred stock, shares outstanding (in shares)	1,952	1,952
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	2,000,000,000	100,000,000	100,000,000
Common stock, shares issued (in shares)	131,863,969	6,154,758	4,522,656
Common stock, shares outstanding (in shares)	131,605,544	5,896,333	4,444,097
Treasury stock, shares	258,425	258,425	78,559

Offerings	Jan. 09, 2026 USD ($)
Offering: 1
Offering:
Fee Previously Paid	false
Rule 457(o)	true
Security Type	Equity
Security Class Title	Units, each consisting of
Maximum Aggregate Offering Price	$ 14,375,000.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 1,985.19
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (3) The proposed maximum aggregate offering price of the units will be reduced on a dollar-for-dollar basis based on the offering price of any pre-funded units issued in the offering, and the proposed maximum aggregate offering price of the pre-funded units to be issued in the offering will be reduced on a dollar-for-dollar basis based on the offering price of any units issued in the offering. Accordingly, the proposed maximum aggregate offering price of the units and pre-funded units (including the shares of common stock issuable upon exercise of the warrants and the pre-funded warrants), if any, is $14,375,000.
Offering: 2
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	(i) One share of common stock
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (4) No separate registration fee is payable pursuant to Rule 457(g) under the Securities Act.
Offering: 3
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	(ii)One warrant to purchase one share of common stock
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (4) No separate registration fee is payable pursuant to Rule 457(g) under the Securities Act.
Offering: 4
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	Pre-funded units, each consisting of
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (3) The proposed maximum aggregate offering price of the units will be reduced on a dollar-for-dollar basis based on the offering price of any pre-funded units issued in the offering, and the proposed maximum aggregate offering price of the pre-funded units to be issued in the offering will be reduced on a dollar-for-dollar basis based on the offering price of any units issued in the offering. Accordingly, the proposed maximum aggregate offering price of the units and pre-funded units (including the shares of common stock issuable upon exercise of the warrants and the pre-funded warrants), if any, is $14,375,000.
Offering: 5
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	(i) one pre-funded warrant to purchase one share of common stock
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (4) No separate registration fee is payable pursuant to Rule 457(g) under the Securities Act.
Offering: 6
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	(ii) one warrant to purchase one share of common stock
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (4) No separate registration fee is payable pursuant to Rule 457(g) under the Securities Act.
Offering: 7
Offering:
Fee Previously Paid	false
Rule 457(o)	true
Security Type	Equity
Security Class Title	Shares of common stock underlying warrants
Maximum Aggregate Offering Price	$ 14,375,000.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 1,985.19
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (3) The proposed maximum aggregate offering price of the units will be reduced on a dollar-for-dollar basis based on the offering price of any pre-funded units issued in the offering, and the proposed maximum aggregate offering price of the pre-funded units to be issued in the offering will be reduced on a dollar-for-dollar basis based on the offering price of any units issued in the offering. Accordingly, the proposed maximum aggregate offering price of the units and pre-funded units (including the shares of common stock issuable upon exercise of the warrants and the pre-funded warrants), if any, is $14,375,000. (5) As estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(g) under the Securities Act, the proposed maximum aggregate offering price of the shares underlying the warrants is equal to $14,375,000 (which is equal to 100% of the proposed maximum aggregate offering price for the units of $14,375,000).
Offering: 8
Offering:
Fee Previously Paid	false
Other Rule	true
Security Type	Equity
Security Class Title	Shares of common stock underlying pre-funded warrants
Maximum Aggregate Offering Price	$ 0.00
Fee Rate	0.01381%
Amount of Registration Fee	$ 0.00
Offering Note	(1) This registration statement also includes an indeterminate number of securities that may become offered, issuable or sold to prevent dilution resulting from stock splits, stock dividends and similar transactions, which are included pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"). (2) Includes the offering price of additional shares of common stock, pre-funded warrants or warrants or any combination thereof that the underwriter has the option to purchase to solely cover over-allotments, if any. (3) The proposed maximum aggregate offering price of the units will be reduced on a dollar-for-dollar basis based on the offering price of any pre-funded units issued in the offering, and the proposed maximum aggregate offering price of the pre-funded units to be issued in the offering will be reduced on a dollar-for-dollar basis based on the offering price of any units issued in the offering. Accordingly, the proposed maximum aggregate offering price of the units and pre-funded units (including the shares of common stock issuable upon exercise of the warrants and the pre-funded warrants), if any, is $14,375,000.

Share-Based Compensation - Stock Option Activity (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Options [Roll Forward]
Balance as of December 31, 2024 (in shares)	598,540	140,109
Granted (in shares)	10,800,137	506,127
Cancelled/forfeited (in shares)	(125,814)	(47,696)
Balance as of September 30, 2025 (in shares)	11,272,863	598,540	140,109
Vested and expected to vest at December 31, 2024 (in shares)	10,073,271	547,893
Exercisable at December 31, 2024	692,781	144,739
Weighted Average Exercise Price [Roll Forward]
Balance as of December 31, 2024 (in dollars per share)	$ 7.08	$ 7.08	$ 37.48
Granted (in dollars per share)	0.61	1.58
Cancelled/forfeited (in dollars per share)	4.5	38.02
Balance as of September 30, 2025 (in dollars per share)	0.91	7.08	$ 7.08
Vested and expected to vest at December 31, 2024 (in dollars per share)	0.94	7.52
Exercisable at December 31, 2024 (in dollars per share)	$ 5.15	$ 22.96
Weighted Average Remaining Contractual Life (years) [Roll Forward]
Balance as of December 31, 2023	9 years 9 months 3 days	9 years	8 years 25 days
Vested and expected to vest at December 31, 2024	9 years 9 months	9 years
Exercisable at December 31, 2024	8 years 11 months 26 days	7 years 7 months 6 days

Term Loan Obligations - Additional Information (Details) - Term Loan [Member] - USD ($) $ in Millions		12 Months Ended
	May 29, 2015	Dec. 31, 2024	Jun. 03, 2024
Debt Instrument [Line Items]
Origination date		May 29, 2015
Original loan amount	$ 17.7
Maturity date	May 01, 2021
Fees amount associated with loan			$ 3.3

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 3
-Subparagraph (SX 210.12-04(a))
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-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.4-08(f))
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
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-Name Accounting Standards Codification
-Section 55
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-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Section 50
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-Subparagraph (a)
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Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-Name Accounting Standards Codification
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-Paragraph 69E
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-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69E

Reference 12: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-Name Accounting Standards Codification
-Section 55
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-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69F

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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+ Details

Short-Term Investments - Summary of Contractual Maturities of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Amortized Cost
Due in one year or less	$ 2,309
Due after one year through five years	0
Due after five years	1,003
Amortized Cost	3,312	$ 3,500
Estimated Fair Value
Due in one year or less	2,309
Due after one year through five years	0
Due after five years	1,003
Estimated Fair Value	$ 3,312

Summary of Significant Accounting Policies - Additional Information (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($) SEGMENT	Dec. 31, 2024 USD ($) SEGMENT ReportableUnit	Dec. 31, 2023 USD ($) SEGMENT	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2022 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Impairment loss		$ 0	$ 0
Stockholders' deficit	$ 5,054,000	$ (8,949,000)	$ (1,348,000)	$ 3,034,000	$ (23,641,000)	$ (5,174,000)	$ (7,625,000)	$ (4,837,000)	$ 6,445,000
Number of reporting units \| ReportableUnit		1
Interest or penalties related to income tax matters		$ 0
Number of operating segment \| SEGMENT	1	1	1
ASU - 2023-07
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adopted		true
Change in accounting principle, accounting standards update, adoption date		Dec. 31, 2024
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful lives of the assets		3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful lives of the assets		5 years

Share-Based Compensation - Summary of Share-Based Compensation Recognized (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 827	$ 422	$ 550	$ 569
Research and Development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense			51	66
General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense			$ 499	$ 503

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Section 35
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-URI https://asc.fasb.org/1943274/2147480483/718-10-35-1D

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
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Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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Reference 29: http://www.xbrl.org/2003/role/disclosureRef
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Composition of Certain Financial Statement Captions - Future Amortization Expense on Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2025	$ 140
2026	136
2027	136
2028	57
Intangible Asset, Net	$ 469	$ 42

Fair Value Measurements - Summary of Key Level 3 Inputs Used in Fair Value (Details) - Convertible Notes [Member]	Mar. 04, 2025	Feb. 13, 2025
Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	3.99
Interest Rate [Member] \| Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input		4.18
Interest Rate [Member] \| Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input		4.28
Remaining Term [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible Notes Term	11 months 8 days	1 year
Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	119.2	77.5
Fair Value of Common Stock [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.3	1.2

Employee Benefit Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Defined Contribution Plan Disclosure [Line Items]
Discretionary or matching contributions	$ 138,000	$ 107,000
Maximum [Member]
Defined Contribution Plan Disclosure [Line Items]
Percentage of matching contribution for employee contributions	4.00%

Loss per Share - Schedule of Antidilutive Securities Excluded from Diluted Loss per Share (Details) - shares	9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Dilutive common shares excluded from the calculations of diluted loss per share (in shares)	17,266,903	1,333,404	7,809,794	311,032
Outstanding Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Dilutive common shares excluded from the calculations of diluted loss per share (in shares)	11,272,863	598,540	598,540	140,109
Outstanding Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Dilutive common shares excluded from the calculations of diluted loss per share (in shares)	2,823,857
Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Dilutive common shares excluded from the calculations of diluted loss per share (in shares)	28,190	28,190	28,190	28,190
Outstanding Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Dilutive common shares excluded from the calculations of diluted loss per share (in shares)	3,141,993	706,674	7,183,064	142,733

Income Taxes (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Summary of Company's Net Loss Before Income Tax Provision

The table below summarizes the Company’s net loss before income tax provision for the years ended December 31, 2024 and 2023 (in thousands):


	2024			2023
Domestic	$	(12,978	)	$	(13,316	)
Foreign		—			—
Net loss before provision for income taxes	$	(12,978	)	$	(13,316	)

Reconciliation of Total Income Tax Provision

A reconciliation of the total income tax provision tax rate to the statutory federal income tax rates of 21.0% for the years ended December 31, 2024 and 2023, respectively, is as follows:


	2024			2023
Income tax expense (benefit) at federal statutory rate		(21.0	)%		(21.0	)%
Change in valuation allowance		23.8	%		25.5	%
Income tax benefit at state statutory rate		(0.3	)%		(0.2	)%
Share-based compensation		0.9	%		1.0	%
Warrants		(2.6	)%		—
NOLs expiring and adjustments to NOL		(0.1	)%		(0.1	)%
Research credit		(0.7	)%		(5.1	)%
Return to provision		—			(0.1	)%

		(0.0	)%		0.0	%

Deferred Tax Assets and Liabilities

The tax effects of temporary differences that give rise to significant portions of our deferred tax assets and deferred tax liabilities as of December 31, 2024 and 2023 are as follows (in thousands):


	2024		2023
Deferred tax assets:
Accrued expenses	$	249	$	269
Share-based compensation		94		99
Net operating loss carryforwards		15,412		13,397
Income tax credit carryforwards		1,725		1,630
Property and equipment, net		218		154
Intangible assets		730		685
Capitalized R&D		3,949		2,842


	2024			2023
Other, net		213			453
Total deferred tax assets		22,590			19,529
Valuation allowance		(22,575	)		(19,486	)

Total deferred tax assets, net of allowance		15			43

Deferred tax liabilities:
Other		(15	)		(43	)

Total deferred tax liability		(15	)		(43	)

Net deferred tax assets (liability)	$	—		$	—

Unrecognized Tax Benefits Activity

Following is a tabular reconciliation of the unrecognized tax benefits activity during the years ended December 31, 2024 and 2023 (in thousands):


	2024			2023
Unrecognized Tax Benefits – Beginning	$	408		$	209
Gross decreases – tax positions in prior period		(5	)		(16	)
Gross increase – current-period tax positions		21			215

Unrecognized Tax Benefits – Ending	$	424		$	408

Stockholders' Equity - Summary of Warrants Outstanding (Details)	Sep. 30, 2025 shares
Class of Warrant or Right [Line Items]
Number of base warrant shares at issuance	5,753,802
May 2024 Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Number of base warrant shares at issuance	48,285
May 2024 Series B Warrants [Member]
Class of Warrant or Right [Line Items]
Number of base warrant shares at issuance	3,093,708
March 2025 Prefunded Warrants [Member]
Class of Warrant or Right [Line Items]
Number of base warrant shares at issuance	2,611,809

Summary of Significant Accounting Policies (Policies)	9 Months Ended	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2025	Dec. 31, 2024
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions affecting the financial statements and the accompanying notes. The Company’s most significant estimates and critical accounting policies involve estimating the fair value of its derivative instruments, reviewing assets for impairment and determining the assumptions used in measuring stock-based compensation expense.	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions affecting the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting period. The most significant estimates and critical accounting policies involve reviewing assets for impairment, and determining the assumptions used in measuring share-based compensation expense and warrant liability. Actual results could differ from these estimates. Management’s estimates and assumptions are reviewed regularly, and the effects of revisions are reflected in the financial statements in the periods they are determined to be necessary.
Cash and cash equivalents		Cash and cash equivalents The Company considers all highly liquid investments with maturities of three months or less at the time of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking, savings accounts and money market accounts. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institution in which those deposits are held.
Financial Instruments		Financial Instruments Financial instruments include cash equivalents, other current assets, accounts payable, accrued expenses, other liabilities and long-term debt. The carrying values of cash equivalents, other current assets, accounts payable, accrued expenses and other liabilities generally approximate fair value due to the short-term nature of these instruments. Based on level 3 inputs and the borrowing rates currently available for loans with similar terms, the Company believes the fair value of the long-term debt is materially consistent with its carrying value.
Property and Equipment		Property and Equipment Property and equipment are stated at cost, net of accumulated depreciation . Depreciation expense, which includes the amortization of capitalized leasehold improvements, is provided for on a straight-line basis over the estimated useful lives of the assets, or the life of the lease, whichever is shorter, and range from three to five years. When assets are sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and the resulting gain or loss, if any, is included in operations. Maintenance and repairs are charged to operations as incurred.
Impairment		Impairment The Company assesses its property and equipment and intangible assets for potential impairment when there is a change in circumstances that indicates carrying values of assets may not be recoverable. Such long-lived assets are deemed to be impaired when the undiscounted cash flows expected to be generated by the asset (or asset group) are less than the asset’s carrying amount. Any required impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value and would be recorded as a reduction in the carrying value of the related asset and a charge to operating expense. The Company recognized no impairment losses during any of the periods presented in these financial statements.
Goodwill		Goodwill The Company’s goodwill represents the excess of the cost over the fair value of net assets acquired from its business combinations. The determination of the value of goodwill arising from business combinations requires extensive use of accounting estimates and judgments to allocate the purchase price to the fair value of the net tangible and intangible assets acquired. Goodwill is not amortized; however, it is assessed for impairment using fair value measurement techniques on an annual basis or more frequently if facts and circumstance warrant such a review. Goodwill is considered to be impaired if the Company determines that the carrying value of the reporting unit exceeds its fair value. The Company performs its impairment test annually during the fourth quarter by comparing the Company’s estimated fair value, calculated from the Company’s market capitalization, to its carrying amount. The Company’s annual evaluation for impairment of goodwill consists of one reporting unit. The Company completed its most recent annual evaluation for impairment as of December 31, 2024, when the Company had stockholders’ deficit within its sole reporting unit of approximately $8.9 million, and concluded that no impairment existed.
Grant Revenue Recognition	Grant Revenue Recognition In applying the provisions of Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”), the Company has determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer”, as defined by ASC 606, as the Company does not consider there to be a transfer of control of goods or services. With respect to each grant, the Company determines if it has a collaboration in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, the Company applies International Accounting Standards No. 20 (“IAS 20”), Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the contract. The Company also considers the guidance in ASC Topic 730, Research and Development, which requires an assessment, at the inception of each grant, of whether each grant agreement is a liability. If the Company is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred. Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date.	Grant Revenue Recognition In applying the provisions of Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”), the Company has determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer,” as defined by ASC 606, as there is not considered to be a transfer of control of goods or services. With respect to the grant, the Company determines if it is a collaboration arrangement in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, the Company applies International Accounting Standards No. 20, Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the contract. The Company also considers the guidance in ASC Topic 730, Research and Development (“ASC 730”), which requires an assessment, at the inception of the grant, of whether the agreement is a liability. If the Company is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred. Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant Receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date.
Research and Development		Research and Development Research and development expenditures, which are charged to operations in the period incurred, include costs associated with the design, development, testing and enhancement of the Company’s products, regulatory fees, the purchase of laboratory supplies, and pre-clinical and clinical studies as well as salaries and benefits for the Company’s research and development employees.
Warrants	Warrants Warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement in accordance with applicable accounting guidance provided in ASC Topic 815, Derivatives and Hedging. Equity-classified instruments are recorded in additional paid-in capital at issuance and are not subject to remeasurement. Liability-classified warrants are recorded at fair value at each reporting period with any change in fair value recognized as a component of change in fair value of derivative liabilities in the condensed consolidated statements of operations. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants.	Warrants Warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement in accordance with applicable accounting guidance provided in ASC Topic 815— Derivatives and Hedging . Equity-classified instruments are recorded in additional paid-in capital at issuance and are not subject to remeasurement. Liability-classified warrants are recorded at fair value at each reporting period with any change in fair value recognized as a component of change in fair value of warrants in the consolidated statements of operations. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants.
Available-for-Sale Securities	Available-for-Sale Securities The Company’s available-for-sale securities consist of U.S. government and agency securities and bonds. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the condensed consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (expense). At each balance sheet date, the Company assesses available-for-sale securities in an unrealized loss position to determine whether the decline in fair value below amortized cost is a result of credit losses or other factors, whether the Company expects to recover the amortized cost of the security, the Company’s intent to sell and if it is more likely than not that the Company will be required to sell the securities before the recovery of amortized cost. The Company records changes in allowance for expected credit loss in other income (expense). There has been no allowance for expected credit losses recorded during any of the periods presented. Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the condensed consolidated statements of operations.	Available-for-Sale Securities The Company’s available-for-sale securities consist of U.S. government and agency securities. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) within the consolidated statements of operations and comprehensive income/loss and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (loss). At each balance sheet date, the Company assesses available-for-sale securities in an unrealized loss position to determine whether the decline in fair value below amortized cost is a result of credit losses or other factors, whether the Company expects to recover the amortized cost of the security, the Company’s intent to sell and if it is more likely than not that the Company will be required to sell the securities before the recovery of amortized cost. The Company records changes in allowance for expected credit loss in other income (expense). There has been no allowance for expected credit losses recorded during any of the periods presented. Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the consolidated statements of operations and comprehensive income/loss. During the year ended December 31, 2024, the total unrealized gains and losses on the Company’s available-for-sale securities were immaterial, and not presented separately in the consolidated statement of operations.
Deferred Financing Costs and Other Debt-Related Costs		Deferred Financing Costs and Other Debt-Related Costs Deferred financing costs are capitalized, recorded as an offset to debt balances and amortized to interest expense over the term of the associated debt instrument using the effective interest method. If the maturity of the debt is accelerated because of default or early debt repayment, then the amortization would be accelerated.
Income Taxes		Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income (loss) in the years in which those temporary differences are expected to be recovered or settled. Due to our history of losses, a full valuation allowance has been recognized against our deferred tax assets. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. For the years ended December 31, 2024 and 2023, the Company has not recorded any interest or penalties related to income tax matters. The Company does not foresee any material changes to unrecognized tax benefits within the next twelve months.
Share-Based Compensation		Share-Based Compensation The Company recognizes the fair value of all share-based payment awards in our statements of operations over the requisite vesting period of each award, which approximates the period during which the employee and non-employee director is required to provide service in exchange for the award. The Company estimates the fair value of these options using the Black-Scholes option pricing model using assumptions for expected volatility, expected term, and risk-free interest rate. Expected volatility is based primarily on historical volatility and is computed using daily pricing observations for recent periods that correspond to the expected term of the options. The expected term represents the period of time that options are expected to be outstanding. Because the Company does not have historical exercise behavior, it determines the expected life assumption using the simplified method which is an average of the contractual term of the option and its vesting period. The risk-free interest rate is the interest rate for treasury instruments with maturities that approximate the expected term.
Segment Information		Segment Information For the years ended December 31, 2024 and 2023, the Company is managed as a single operating segment, and therefore reports its results in one operating segment.
Loss Per Share		Loss Per Share Basic per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period increased to include, if dilutive, the number of additional common shares that would have been outstanding as calculated using the treasury stock method. Potential common shares were related entirely to outstanding but unexercised options, warrants and convertible preferred stocks for all periods presented.
Concentration Risk		Concentration Risk Although the Company’s contracts with its vendors are not exclusive, the Company currently uses sole source providers for core materials used in its clinical trials.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In December 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) No. 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosure. This ASU includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The ASU is effective for years beginning after December 15, 2024, but early adoption is permitted. This ASU should be applied on a prospective basis, although retrospective application is permitted. The Company adopted this ASU as of January 1, 2025 which did not have a material impact on the Company’s consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03 Income Statement (Topic 220): Reporting Comprehensive Income - Expense Disaggregation Disclosures, which requires an entity to disclose on an annual and interim basis, disaggregated information about specific income statement expense categories. The guidance should be applied prospectively with the option to apply the standard retrospectively. The standard becomes effective for the annual period starting on January 1, 2027 and interim periods starting on January 1, 2028. The Company is in the process of analyzing the impact that the adoption of ASU 2024-03 will have on its disclosures.	Recently Issued Accounting Pronouncements In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The new standard is intended to improve annual and interim reportable segment disclosure requirements regardless of number of reporting units, primarily through enhanced disclosures of significant expenses. The amendment requires public entities to disclose significant segment expenses that are regularly provided to the Company’s chief operating decision maker (“CODM”) and included within each reported measure of segment profit and loss. This update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years starting after December 15, 2024. This ASU must be applied retrospectively to all prior periods presented. Management adopted this ASU as of December 31, 2024 and included additional disclosures as required in the footnotes to this annual report on Form 10-K. In December 2023, the FASB issued ASU No. 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosure. This ASU includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The ASU is effective for years beginning after December 15, 2024, but early adoption is permitted. This ASU should be applied on a prospective basis, although retrospective application is permitted. Management does not expect the adoption of this ASU to have a material impact on the Company’s consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03 Income Statement (Topic 220): Reporting Comprehensive Income—Expense Disaggregation Disclosures, which requires an entity to disclose on an annual and interim basis, disaggregated information about specific income statement expense categories. The guidance should be applied prospectively with the option to apply the standard retrospectively. The standard becomes effective for the annual period starting on January 1, 2027 and interim periods starting on January 1, 2028. The Company is in the process of analyzing the impact that the adoption of ASU 2024-03 will have on its disclosures.

Fair Value Measurements

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

4. Fair

Value Measurements

Fair value measurements are market-based measurements, not entity-specific measurements. Therefore, fair value measurements are determined based on the assumptions that market participants would use in pricing the asset or liability. The Company follows a three-level hierarchy to prioritize the inputs used in the valuation techniques to derive fair values. The basis for fair value measurements for each level within the hierarchy is described below:

•

Level 1: Quoted prices in active markets for identical assets or liabilities.

•

Level 2: Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs are observable in active markets.

•

Level 3: Valuations derived from valuation techniques in which one or more significant inputs are unobservable in active markets.

Assets recorded at fair value

The Company has investments in money market accounts which are included in cash and cash equivalents and investments, respectively, on the condensed consolidated balance sheets. Money market accounts are considered Level 1 measurements within the fair value hierarchy since money market account fair values are known and observable through daily published floating net asset values.

The following table summarizes the Company’s fair value hierarchy for its financial assets measured at fair value on a recurring basis as of September 30, 2025 and December 31, 2024, respectively (in thousands):


	Fair Value Measurements Using
September 30, 2025	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	15	$	15	$	—	$	—

Investments
Treasury bills	$	2,309	$	—	$	2,309	$	—
Government bonds		1,003		1,003		—		—

Total Investments	$	3,312	$	1,003	$	2,309	$	—


	Fair Value Measurements Using
December 31, 2024	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	74	$	74	$	—	$	—

Investments
Treasury bills		2,062		—		2,062		—
Government agency bonds		772		772		—		—
Money market		696		696		—		—

Total Investments	$	3,530	$	1,468	$	2,062	$	—

Liabilities recorded at fair value

Convertible Notes

As detailed in Note 13 below, the Company elected to account for convertible notes (consisting of funding notes and exchange notes) issued on February 13, 2025 at fair value as of the issuance date and immediately before their settlement date of March 4, 2025. The convertible notes are valued using the binomial lattice model with the following key level 3 inputs:


	At issuance	At settlement
Interest rate	4.18%-4.28%		3.99	%
Remaining term (years)	1.0		0.94
Volatility	77.5%		119.2	%
Fair value of common stock	$1.20	$	0.30

The following table provides a roll forward of the fair value of the convertible notes during the nine months ended September 30, 2025 (in thousands):


	Funding Notes			Exchange Notes
Beginning balance as of January 1, 2025	$	—		$	—
Issuance		3,968			3,763
Change in fair value		(265	)		(251	)
Settlement		(3,703	)		(3,512	)

Ending balance as of September 30, 2025	$	—		$	—

War

ran

As detailed in Note 13 below, the Company issued March 2025 Series A and March 2025 Series B common stock warrants in connection with the March 2025 Private Placement. The March 2025 Series A and March 2025 Series B common stock warrants are accounted for as liabilities at fair value at issuance date, and immediately prior to their extinguishment and modification, respectively, on June 17, 2025. The March 2025 Series A and March 2025 Series B common stock warrants were valued using the Monte Carlo simulation, with the following key level 3 inputs:


	At issuance			At modification and extinguishment
Interest rate		3.98	%		3.91	%
Remaining term (years)		6.1			4.9
Volatility		123.7	%		135.6	%

The March 2025 Series B Warrants were valued immediately prior to exercise, using the Monte Carlo simulation with the following inputs for the exercises that occurred before the modification on June 17, 2025:


		At exercise
Interest rate		3.85% - 4.06%
Remaining term (years)		4.9 - 5.0
Volatility		133.9% - 135.8%

In addition, the February 2025 Warrants issued in connection with the Funding Notes were required to be classified as liabilities and recorded at fair value. The Company estimated the fair value of the February 2025 Warrants using the Black Scholes model at issuance as of February 13, 2025 and as of their redemption date of March 4, 2025, using the following level 3 inputs:


	At issuance			At settlement
Interest rate		4.30	%		4.30	%
Remaining term (years)		5.0			4.95
Volatility		98.5	%		102.1	%
Fair value of common stock	$	1.20		$	0.30

The following table provides a roll forward of the fair value of liability classified common stock warrants during the nine months ended September 30, 2025 (in thousands):


	February 2025 Warrants			March 2025 Series A Warrants			March 2025 Series B Warrants			Total
Beginning balance as of January 1, 2025	$	—		$	—		$	—		$	—
Issuance		2,762			2,005			11,243			16,010
Change in fair value		(2,231	)		335			5,043			3,147
Settlement		(531	)		—			(858	)		(1,389	)
Modification and extinguishment		—			(2,340	)		(4,461	)		(6,801	)
Reclassified to equity		—			—			(10,967	)		(10,967	)

Ending balance as of September 30, 2025	$	—		$	—		$	—		$	—

3. Fair Value Measurements

•

Level 1: Quoted prices in active markets for identical assets or liabilities.

•

Level 3: Valuations derived from valuation techniques in which one or more significant inputs are unobservable in active markets.

The Company has investments in money market accounts, which are included in cash and cash equivalents on the balance sheets. Fair value inputs for these investments are considered Level 1 measurements within the fair value hierarchy since money market account fair values are known and observable through daily published floating net asset values.

The following table summarizes the Company’s fair value hierarchy for its financial assets measured at fair value on a recurring basis as of December 31, 2024 and December 31, 2023, respectively (in thousands).


	Fair Value Measurements Using
December 31, 2024	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	74	$	74	$	—	$	—

Total cash equivalents	$	74	$	74	$	—	$	—

Investments
Treasury bills		2,062		—		2,062		—
Government agency bonds		772		772		—		—
Money market		696		696		—		—

Total investments	$	3,530	$	1,468	$	2,062	$	—


	Fair Value Measurements Using
December 31, 2023	Fair Value		Level 1		Level 2		Level 3
Money market	$	5,449	$	5,449	$	—	$	—

During the year ended December 31, 2024, the Company issued common stock warrants which were initially classified as liabilities under authoritative accounting standards, and reclassified in the equity section of the balance sheet upon modification in August 2024 (See Note 15, Stockholders’ Deficit—May 2024 Private Placement, for further details). These common stock warrants were valued using the Black Scholes model, with level 3 inputs such as expected volatility, risk-free interest rate, and expected term that are not observable in active markets.

The table below summarizes key inputs used in the valuation of the liability classified warrants as of the issuance date and as of the date of amendment:


	As of issuance date		As of date of amendment
Expected term		1.1 - 5.0 years		0.9 - 4.7 years
Common stock market price		$ 2.01 - $ 2.27		$ 1.45
Risk-free interest rate		4.5 % - 5.1 %		3.81 % - 4.63 %
Expected volatility		117.0 % - 127.2 %		92.2 % - 99.79 %

The table below provides a summary of the fair value of the Company’s warrant liability during year ended December 31, 2024 (in thousands). As of December 31, 2023, the fair value of liability classified warrants was immaterial, and the change in the fair value of liability classified warrants during the year ended December 31, 2023 was immaterial.


	Twelve Months Ended December 31, 2024
Warrant liability
Beginning balance	$	—
Issuance of warrants		10,854
Change in fair value of warrants		(5,654	)
Reclassification to equity		(5,200	)

Ending balance	$	—

Nonfinancial Assets and Liabilities

The Company applies fair value techniques on a

non-recurring

basis, if and when necessary, associated with: (1) valuing potential impairment losses related to goodwill and intangible assets which are accounted

for pursuant

to the authoritative guidance for intangibles—goodwill and other; and (2) valuing potential impairment losses related to long-lived assets which are accounted for pursuant to the authoritative guidance for property, plant and equipment. There was

impairment related to long lived assets, intangible assets, or goodwill during the years ended December 31, 2024 or 2023.

Fair Value Measurements (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Summary of Financial Assets Measured at Fair Value on Recurring Basis


	Fair Value Measurements Using
September 30, 2025	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	15	$	15	$	—	$	—

Investments
Treasury bills	$	2,309	$	—	$	2,309	$	—
Government bonds		1,003		1,003		—		—

Total Investments	$	3,312	$	1,003	$	2,309	$	—


	Fair Value Measurements Using
December 31, 2024	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	74	$	74	$	—	$	—

Investments
Treasury bills		2,062		—		2,062		—
Government agency bonds		772		772		—		—
Money market		696		696		—		—

Total Investments	$	3,530	$	1,468	$	2,062	$	—


	Fair Value Measurements Using
December 31, 2024	Fair Value		Level 1		Level 2		Level 3
Cash equivalents
Money market	$	74	$	74	$	—	$	—

Total cash equivalents	$	74	$	74	$	—	$	—

Investments
Treasury bills		2,062		—		2,062		—
Government agency bonds		772		772		—		—
Money market		696		696		—		—

Total investments	$	3,530	$	1,468	$	2,062	$	—


	Fair Value Measurements Using
December 31, 2023	Fair Value		Level 1		Level 2		Level 3
Money market	$	5,449	$	5,449	$	—	$	—

Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value

The table below summarizes key inputs used in the valuation of the liability classified warrants as of the issuance date and as of the date of amendment:


	As of issuance date		As of date of amendment
Expected term		1.1 - 5.0 years		0.9 - 4.7 years
Common stock market price		$ 2.01 - $ 2.27		$ 1.45
Risk-free interest rate		4.5 % - 5.1 %		3.81 % - 4.63 %
Expected volatility		117.0 % - 127.2 %		92.2 % - 99.79 %

Schedule of Change in Fair Value of Liability

The following table provides a roll forward of the fair value of liability classified common stock warrants during the nine months ended September 30, 2025 (in thousands):


	February 2025 Warrants			March 2025 Series A Warrants			March 2025 Series B Warrants			Total
Beginning balance as of January 1, 2025	$	—		$	—		$	—		$	—
Issuance		2,762			2,005			11,243			16,010
Change in fair value		(2,231	)		335			5,043			3,147
Settlement		(531	)		—			(858	)		(1,389	)
Modification and extinguishment		—			(2,340	)		(4,461	)		(6,801	)
Reclassified to equity		—			—			(10,967	)		(10,967	)

Ending balance as of September 30, 2025	$	—		$	—		$	—		$	—


	Twelve Months Ended December 31, 2024
Warrant liability
Beginning balance	$	—
Issuance of warrants		10,854
Change in fair value of warrants		(5,654	)
Reclassification to equity		(5,200	)

Ending balance	$	—

Convertible Notes [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value


	At issuance	At settlement
Interest rate	4.18%-4.28%		3.99	%
Remaining term (years)	1.0		0.94
Volatility	77.5%		119.2	%
Fair value of common stock	$1.20	$	0.30

Schedule of Change in Fair Value of Liability

The following table provides a roll forward of the fair value of the convertible notes during the nine months ended September 30, 2025 (in thousands):


	Funding Notes			Exchange Notes
Beginning balance as of January 1, 2025	$	—		$	—
Issuance		3,968			3,763
Change in fair value		(265	)		(251	)
Settlement		(3,703	)		(3,512	)

Ending balance as of September 30, 2025	$	—		$	—

War

ran

March 2025 Series A and B Warrants [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value


	At issuance			At modification and extinguishment
Interest rate		3.98	%		3.91	%
Remaining term (years)		6.1			4.9
Volatility		123.7	%		135.6	%

Series B Warrants [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value


		At exercise
Interest rate		3.85% - 4.06%
Remaining term (years)		4.9 - 5.0
Volatility		133.9% - 135.8%

February 2025 Warrants [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Summary of Key Level 3 Inputs Used in Valuation of Warrants Liability at Fair Value


	At issuance			At settlement
Interest rate		4.30	%		4.30	%
Remaining term (years)		5.0			4.95
Volatility		98.5	%		102.1	%
Fair value of common stock	$	1.20		$	0.30

Loss per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share of Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Basic and diluted net loss per share of common stock calculation:
Net loss	$ (4,423)	$ 5,151	$ (17,401)	$ (2,874)	$ (2,940)	$ (3,261)	$ (16,673)	$ (9,075)	$ (12,978)	$ (13,316)
Change in fair value of warrants									(5,047)
Change in fair value of derivative instruments								(5,047)
Net loss attributable to common stockholders - basic	$ (4,423)			$ (2,874)			$ (16,673)	$ (14,122)
Net loss attributable to common stockholders - diluted									$ (18,025)	$ (13,316)
Weighted average common shares outstanding - basic	107,428,969			7,855,763			57,845,406	6,232,123	6,640,251	3,140,925
Net loss per share of common stock - basic	$ (0.04)			$ (0.37)			$ (0.29)	$ (1.46)	$ (1.95)	$ (4.24)
Weighted average common shares outstanding - diluted	107,428,969			7,855,763			57,845,406	8,452,338	7,700,774	3,140,925
Net loss per share of common stock - diluted	$ (0.04)			$ (0.37)			$ (0.29)	$ (1.67)	$ (2.34)	$ (4.24)

Stock-Based Compensation - Stock Option Activity (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Options [Roll Forward]
Balance as of December 31, 2024 (in shares)	598,540	140,109
Granted (in shares)	10,800,137	506,127
Cancelled/forfeited/expired (in shares)	(125,814)	(47,696)
Balance as of September 30, 2025 (in shares)	11,272,863	598,540	140,109
Vested and expected to vest at September 30, 2025 (in shares)	10,073,271	547,893
Exercisable at September 30, 2025 (in shares)	692,781	144,739
Weighted Average Exercise Price [Roll Forward]
Balance as of December 31, 2024 (in dollars per share)	$ 7.08	$ 7.08	$ 37.48
Granted (in dollars per share)	0.61	1.58
Cancelled/forfeited (in dollars per share)	4.5	38.02
Balance as of September 30, 2025 (in dollars per share)	0.91	7.08	$ 7.08
Vested and expected to vest at September 30, 2025 (in dollars per share)	0.94	7.52
Exercisable at September 30, 2025 (in dollars per share)	$ 5.15	$ 22.96
Weighted Average Remaining Contractual Life (years) [Roll Forward]
Balance as of September 30, 2025	9 years 9 months 3 days	9 years	8 years 25 days
Vested and expected to vest at September 30, 2025	9 years 9 months	9 years
Exercisable at September 30, 2025	8 years 11 months 26 days	7 years 7 months 6 days
Aggregated Intrinsic Value [Roll Forward]
Balance as of December 31, 2024	$ 0
Cancelled/forfeited/expired	0
Balance as of September 30, 2025	1,103	$ 0
Vested and expected to vest as of September 30, 2025	980
Exercisable at September 30, 2025	$ 33

Investments	12 Months Ended
Investments	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Investments	4. Investments As of December 31, 2024, the Company had total investments of $3.5 million of money market accounts, treasury bills, and government agency bonds, with total amortized cost and fair value of $ 3.5 million. These investments are collateralized marketable securities as described in footnote 10. The Company did not have investments as of December 31, 2023. As of December 31, 2024, the Company classified available-for-sales as short-term investments in the consolidated balance sheet because the maturity dates were less than one year from the date of the purchase.

Commitments and Contingencies

9 Months Ended

12 Months Ended

Sep. 30, 2025

Dec. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

8. Commitments and Contingencies

Leases

The Company leases certain office space in Charlottesville, Virginia (the “Charlottesville Lease”). The Charlottesville Lease expires on March 31, 2026.

Manufacturing Agreement with SpectronRx

On November 5, 2024, the Company entered into a manufacturing services agreement with SpectronRx for drug product development and manufacturing, which includes an initial commitment fee of $0.3 million. Under this agreement, the Company owns all rights to intellectual property related to the products developed, while SpectronRx retains rights to its own technology. SpectronRx is required to negotiate a commercial supply agreement upon six months’ written notice before the Company’s first commercial manufacturing needs. The agreement will remain in place for five years, automatically renewing for successive

one-year

terms unless terminated with six months’ notice. During the nine months ended September 30, 2025 and year ended December 31, 2024, the Company did not recognize any expenses related to this agreement.

Other commitments and contingencies

The Company has entered into agreements with various research organizations for preclinical and clinical development studies, which have provisions for cancellation. Under the terms of these agreements, the vendors provide a variety of services including conducting research, recruiting and enrolling patients, monitoring studies and data analysis. Payments under these agreements typically include fees for services and reimbursement of expenses. The timing of payments due under these agreements is estimated based on study progress. As of September 30, 2025, the Company did

t have any clinical research study obligations.

The Company has entered into service and subscription-based agreements, which are recorded in accounts payable and accrued expenses, with an offsetting amount included in deferred costs within other current assets.

Legal proceedings

From time to time, the Company is subject to legal proceedings and claims, whether asserted or unasserted, that arise in the ordinary course of business. Due to their nature, such legal proceedings involve inherent uncertainties including, but not limited to, court rulings, negotiations between affected parties and governmental actions. Management assesses the probability of loss for such contingencies and accrues a liability and/or discloses the relevant circumstances, as appropriate.

7. Commitments and Contingencies

Leases

At the inception of a contractual arrangement, the Company determines whether the contract contains a lease by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company calculates the associated lease liability and corresponding

right-of-use

asset upon lease commencement using a discount rate based on the rate implicit in the lease or an incremental borrowing rate commensurate with the term of the lease. Lease renewable options are included in the estimation of lease term when it is reasonably certain that the Company will exercise such options.

The Company records lease liabilities within current liabilities or long-term liabilities based upon the length of time associated with the lease payments. The Company records its operating lease

right-of-use

assets as long-term assets. Leases with an initial term of 12 months or less are not recorded on the balance sheets. Instead, the Company recognizes lease expense for these leases on a straight-line basis over the lease term in the statements of operations.

The Company leased laboratory, office and storage facilities in San Antonio, Texas, under operating lease agreements that expire in 2025. The Company also leased, through December 31, 2024, certain office space in Austin, Texas under a

month-to-month

operating lease agreement and certain office space in Charlottesville, Virginia (the “Charlottesville Lease”). The Company’s existing operating lease agreements generally provide for periodic rent increases, and renewal and termination options. The Company’s lease agreements do not contain any material variable lease payments, residual value guarantees or material restrictive covenants.

The Charlottesville Lease has a term of 12 months and the Company has the ability to

rene

w for three additional

one-year

periods. On March 31, 2023, Company believed that it was reasonably certain that the Charlottesville Lease will be renewed through March 31, 2026, and as a result, it remeasured the related

lease liability

as of March 31, 2023 to be $

80,000

using the

then-in-effect

discount rate of

12.76

%. Effective July 1, 2023, the Company added additional office lease premises in Charlottesville, which was accounted for as a separate operating lease contract with a lease liability and corresponding

right-of-use

asset of $

19,000

, at a discount rate of

13.47

Certain leases require the Company to pay taxes, insurance, and maintenance. Payments for the transfer of goods or services such as common area maintenance and utilities represent

non-lease

components. The Company elected the package of practical expedients and therefore does not separate

non-lease

components from lease components.

The Company’s operating lease liabilities and corresponding

right-of-use

assets are included in the balance sheets. As of December 31, 2024, the weighted average discount rate used to measure operating lease liabilities and the operating leases remaining term were 11.6% and 0.9 years, respectively.

The table below summarizes the Company’s operating lease costs from its statements of operations, and cash payments from its statements of cash flows (in thousands).


	Year Ended December 31,
	2024		2023
Lease expense:
Operating lease expense	$	145	$	141

Total lease expense	$	145	$	141

Cash payment information:
Operating cash used for operating leases	$	180	$	141

Total cash paid for amounts included in the measurement of lease liabilities	$	180	$	141

Total rent expenses for each of the years ended December 31, 2024 and 2023 was $0.2 million, which includes leases in the table above,

month-to-month

operating leases, and common area maintenance charges.

The Company’s future minimum annual lease payments under operating leases at December 31, 2024 are as follows (in thousands):


	Operating Leases
2025	$	69
2026		11

Total minimum lease payments		80

Less: amount representing interest	$	(5	)

Present value of obligations under leases		75

Less: current portion		44

Noncurrent lease obligations	$	31

Manufacturing Agreement with SpectronRX

SpectronRx is required to negotiate a commercial supply agreement upon six months’ written notice before the Company’s first commercial manufacturing needs. The agreement will remain in place for five years,

automatically renewing for successive

one-year

terms unless terminated with six months’ notice. During the year ended December 31, 2024, the Company did not recognize any expenses related to this agreement.

Other Commitments and Contingencies

The Company has entered into agreements with various research organizations for

pre-clinical

and clinical development studies, which have provisions for cancellation. Under the terms of these agreements, the vendors provide a variety of services including conducting research, recruiting and enrolling patients, monitoring studies and data analysis. Payments under these agreements typically include fees for services and reimbursement of expenses. The timing of payments due under these agreements is estimated based on current study progress. As of December 31, 2024, the Company did

not

have any clinical research study obligations.

Legal proceedings

The Company is subject to various claims and contingencies related to legal proceedings. Due to their nature, such legal proceedings involve inherent uncertainties including, but not limited to, court rulings, negotiations between affected parties and governmental actions. Management assesses the probability of loss for such contingencies and accrues a liability and/or discloses the relevant circumstances, as appropriate.