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Preferred Stock and Stockholders' Equity (Tables) | 6 Months Ended
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Jun. 30, 2025
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, 2024 |  |  | 15,778,451 |  |  |  | 17,274,293 |  |  |  | 33,052,744 |
Issued |  |  | — |  |  |  | — |  |  |  | — |
Exercised |  |  | — |  |  |  | — |  |  |  | — |
Cancelled/Expired |  |  | — |  |  |  | — |  |  |  | — |
Balance as of June 30, 2025 |  |  | 15,778,451 |  |  |  | 17,274,293 |  |  |  | 33,052,744 |
Schedule of Company's Outstanding Warrants to Purchase Shares of Common Stock | The following table summarizes the outstanding warrants as of June 30, 2025:
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 June 30, 2025 |  |  | 33,052,744 |  |  |  |  |  |
Preferred Stock Warrants [Member] |
Class Of Stock [Line Items] |
Schedule of Warrants to Purchase Common Stock Activity | As of June 30, 2025, 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 Non-Voting Convertible Preferred Warrant Activity |
|  | Total |
Balance as of December 31, 2024 |  |  | 50,207.419 |
Issued |  |  | — |
Exercised |  |  | — |
Balance as of June 30, 2025 |  |  | 50,207.419 |
The Series X 1 Preferred Stock Warrants were issued on September 14, 2020, with an exercise price of $8.96 and an expiration date of September 14, 2025.
Securities Purchase Agreement [Member] |
Class Of Stock [Line Items] |
Schedule of Assumptions Used in Black-Scholes Option Pricing Model to Determine Fair Value of Stock Options Granted | The following table presents the assumptions used in the Black-Scholes option pricing model to determine the fair value of the Common Warrants as of June 30, 2025 and December 31, 2024 as follows:
|  | June 30, 2025 |  |  | December 31, 2024 |
Risk-free interest rate |  | 3.7% |  |  | 4.4% |
Expected stock price volatility |  | 86.5% |  |  | 96.4% |
Expected term (in years) |  | 3.0 |  |  | 3.5 |
Share price |  | $ | 2.71 |  |  | $ | 4.14 |

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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://www.xbrl.org/2009/role/commonPracticeRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481112/505-10-50-3 + Details
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