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Stockholders' Equity (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2024
Class Of Stock [Line Items] |
Schedule of Assumptions Used in Black-Scholes Option Pricing Model to Determine the Fair Value of Stock Options, Common Warrants and Subsequent Closing Warrants Granted | The Company estimates the fair value of stock option awards on the grant date using the Black-Scholes option pricing model with the following weighted-average assumptions:
|  | Year Ended December 31,
|  | 2024 |  | 2023
Expected stock price volatility |  | 101.3% |  | 90.5%
Risk-free interest rate |  | 4.2% |  | 3.7%
Expected life of options (in years) |  | 6.9 |  | 6.1
Estimated dividend yield |  | —% |  | —%
Schedule of Company's Outstanding Warrants to Purchase Shares of Common Stock | As of December 31, 2024, the Company's outstanding warrants to purchase shares of common stock consisted of the following:
Date Issued |  | Number of Shares of Common Stock Issuable |  |  | Exercise Price |  |  | Expiration Date
January 2020 common warrants |  |  | 5,586 |  |  | $ | 18.90 |  |  | July 14, 2025
January 2020 common warrants |  |  | 3,591 |  |  | $ | 18.90 |  |  | July 17, 2025
January 2020 common warrants |  |  | 247,264 |  |  | $ | 12.96 |  |  | July 14, 2025
January 2020 common warrants |  |  | 71,800 |  |  | $ | 12.96 |  |  | July 17, 2025
September 2020 common warrants |  |  | 298,692 |  |  | $ | 3.08 |  |  | September 14, 2025
2023 Securities Purchase Agreement common warrants |  |  | 15,151,518 |  |  | $ | 3.00 |  |  | May 5, 2028
January 2021 pre-funded warrants |  |  | 509,117 |  |  | $ | 0.001 |  |  | December 31, 2030
2023 Securities Purchase Agreement pre-funded warrants |  |  | 3,844,153 |  |  | $ | 0.001 |  |  | N/A
2024 Securities Purchase Agreement pre-funded warrants |  |  | 7,989,516 |  |  | $ | 0.001 |  |  | N/A
2024 Underwritten Offering pre-funded warrants |  |  | 4,931,507 |  |  | $ | 0.001 |  |  | N/A
Balance as of December 31, 2024 |  |  | 33,052,744 |  |  |  |  |  |
Common Stock Warrants [Member] |
Class Of Stock [Line Items] |
Schedule of Warrants to Purchase Common Stock Activity | The following table shows the warrants to purchase common stock activity:
|  | Roll-Forward of Warrant Activity |
|  | Common Stock Warrants |  |  | Pre-Funded Warrants |  |  | Total |
Balance as of December 31, 2023 |  |  | 15,788,032 |  |  |  | 5,776,270 |  |  |  | 21,564,302 |
Issued |  |  | — |  |  |  | 12,921,023 |  |  |  | 12,921,023 |
Exercised |  |  | — |  |  |  | (1,423,000 | ) |  |  | (1,423,000 | )
Cancelled/Expired |  |  | (9,581 | ) |  |  | — |  |  |  | (9,581 | )
Balance as of December 31, 2024 |  |  | 15,778,451 |  |  |  | 17,274,293 |  |  |  | 33,052,744 |
Preferred Stock Warrants [Member] |
Class Of Stock [Line Items] |
Schedule of Warrants to Purchase Common Stock Activity | As of December 31, 2024, there were 50,207.419 warrants exercisable into Series X 1 Preferred Stock which are convertible into 2,789,301 shares of common stock (after rounding for fractional shares and subject to beneficial ownership limitations).
|  | Roll-Forward of Series X 1 Convertible Preferred Warrant Activity |
|  | Total |
Balance as of December 31, 2023 |  |  | 50,207.419 |
Assumed and replaced |  |  | — |
Exercised |  |  | — |
Cancelled/Expired |  |  | — |
Balance as of December 31, 2024 |  |  | 50,207.419 |
Securities Purchase Agreement [Member] |
Class Of Stock [Line Items] |
Schedule of Assumptions Used in Black-Scholes Option Pricing Model to Determine the Fair Value of Stock Options, Common Warrants and Subsequent Closing Warrants Granted | The following table presents the assumptions used in the Black-Scholes option pricing model to determine the fair value of Common Warrants and Subsequent Closing Warrants granted as of December 31, 2024, and as of the issuance date:
|  | Year Ended December 31, |
|  | 2024 |  |  | 2023 |
Expected stock price volatility |  | 96.4% |  |  | 89.1% - 94.3% |
Risk-free interest rate |  | 4.4% |  |  | 3.8% - 3.9% |
Expected life of options (in years) |  | 3.5 |  |  | 4.5 - 6.0 |
Share price |  | $ | 4.14 |  |  | $ | 1.80 |

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Subparagraph (f)(2) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-1 + Details
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