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Stockholders' Equity (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Summary of Stock Option Activities | The following table summarizes stock option activities for the years ended December 31, 2024 and 2023: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​ | ​ |  | Weighted Average
​ | ​ | ​ | ​ | ​ | ​ | ​ | Remaining
​ | ​ | ​ | ​ | Weighted Average | ​ | Contractual Life (in
​ | ​ | Stock Options | ​ | Exercise Price | ​ | years)
Outstanding at December 31, 2023 |  | 1,521 | ​ | $ | 4,297.50 |  | 3.31
Outstanding at December 31, 2024 |  | 1,521 | ​ | $ | 4,297.50 |  | 2.31
Options vested and exercisable at December 31, 2024 |  | 951 | ​ | $ | 4,297.50 |  | 2.31
Schedule of Stock-Based Compensation Expense | The following table summarizes stock-based compensation expense for the years ended December 31, 2024 and 2023 (in thousands). ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the year ended December 31, | ​
​ |  | 2024 |  | 2023 |
General and administrative | ​ | $ | 200 | ​ | $ | 436 | ​
Research and development | ​ |  | (650) | ​ |  | 132 | ​
Total stock-based compensation expense | ​ | $ | (450) | ​ | $ | 568 | ​
Summary of Warrant Activities | A summary of warrant activities for the years ended December 31, 2024 and 2023, is presented below: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​ | ​ |  | Weighted Average
​ | ​ | ​ | ​ | ​ | ​ | ​ | Remaining
​ | ​ | ​ | ​ | Weighted Average | ​ | Contractual Life (in
​ | ​ | Warrants | ​ | Exercise Price | ​ | years)
Outstanding as of December 31, 2022 |  | 1,387 | ​ | $ | 1,152.94 |  | 8.29
Expired | ​ | (1) | ​ | ​ | 0.08 | ​ | —
Granted |  | 88,232 | ​ |  | 50.09 |  | 5.29
Outstanding as of December 31, 2023 |  | 89,618 | ​ | $ | 67.16 |  | 5.34
Exercised |  | (747,368) | ​ |  | 5.35 |  | —
Granted |  | 2,234,669 | ​ |  | 10.93 |  | 2.10
Outstanding as of December 31, 2024 |  | 1,576,919 | ​ | $ | 14.56 |  | 3.14
Schedule of key inputs used for the Black-Scholes Model calculation to measure the fair value the New Warrants | The key inputs used for the Black-Scholes Model calculation on October 25, 2024, to measure the fair value of the New Warrants, were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | New Series B-1 | ​ | New Series B-2
​ | ​ | Warrants | ​ | Warrants
Stock Price | ​ | 14.50 | ​ | ​ | 14.50 | ​
Risk-free interest rate | ​ | 4.1 | % | ​ | 4.3 | %
Expected dividend yield | ​ | — | ​ | ​ | — | ​
Expected term in years | ​ | 5 | ​ | ​ | 1 | ​
Expected volatility | ​ | 122.2 | % | ​ | 213.2 | %
Restricted stock award |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedules of Restricted Stock and Restricted Stock Unit Activity | Certain employees and directors have been awarded restricted stock. The restricted stock vesting consists of milestone and time-based vesting. The following table summarizes restricted stock award activities for the years ended December 31, 2024 and 2023: ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | Weighted Average
​ | ​ | ​ | ​ | Grant Date Fair
​ | ​ | Number of Shares | ​ | Value
Nonvested at December 31, 2022 |  | 675 | ​ | $ | 1,107.83
Granted | ​ | 720 | ​ | ​ | 345.00
Vested | ​ | (110) | ​ | ​ | 2,310.00
Nonvested at December 31, 2023 |  | 1,285 | ​ | $ | 577.50
Vested | ​ | (90) | ​ | ​ | 2,722.50
Nonvested at December 31, 2024 |  | 1,195 | ​ | $ | 415.95
Restricted stock units |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedules of Restricted Stock and Restricted Stock Unit Activity | The following table summarizes restricted stock units’ activities for the year ended December 31, 2024 and 2023: ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | Weighted Average
​ | ​ | ​ | ​ | Grant Date Fair
​ | ​ | Number of Units | ​ | Value
Nonvested at December 31, 2022 |  | 3,303 | ​ | $ | 1,391.48
Granted |  | 577 | ​ |  | 256.51
Forfeited | ​ | (1,027) | ​ | ​ | 1,374.25
Vested | ​ | (942) | ​ | ​ | 1,614.25
Nonvested at December 31, 2023 |  | 1,911 | ​ | $ | 948.25
Forfeited | ​ | (1,320) | ​ | ​ | 911.70
Vested |  | (365) | ​ |  | 1,205.20
Nonvested at December 31, 2024 |  | 226 | ​ | $ | 746.70

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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -SubTopic 10 -Topic 718 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (e) -SubTopic 10 -Topic 718 -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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