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Fair Value Measurements (Tables) | 9 Months Ended
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Sep. 30, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Summary of Financial Assets Measured at Fair Value on Recurring Basis | 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 |  | $ | — |
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 | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
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 | 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 |
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 |  | $ | — |  |  | $ | — |
Warrants
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 | 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 | %
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 | 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%
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 | 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 |

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- Definition Tabular disclosure of input and valuation technique used to measure fair value and change in valuation approach and technique for each separate class of asset and liability measured on recurring and nonrecurring basis. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 103 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-103 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Tabular disclosure of assets, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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