Stockholders' Equity (Tables)
|
12 Months Ended |
Dec. 31, 2023 |
|---|
| 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, 2023 and 2022:
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Weighted Average |
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Remaining |
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Weighted Average |
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Contractual Life (in |
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|
Stock Options |
|
Exercise Price |
|
years) |
Outstanding at December 31, 2021 |
|
76,112 |
|
$ |
85.95 |
|
5.31 |
Outstanding at December 31, 2022 |
|
76,112 |
|
$ |
85.95 |
|
4.31 |
Outstanding at December 31, 2023 |
|
76,112 |
|
$ |
85.95 |
|
3.31 |
Options vested and exercisable at December 31, 2023 |
|
47,570 |
|
$ |
85.95 |
|
3.31 |
|
| Schedule of Stock-Based Compensation Expense |
The following table summarizes stock-based compensation expense for the years ended December 31, 2023 and 2022 (in thousands).
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For the year ended December 31, |
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|
2023 |
|
2022 |
General and administrative |
|
$ |
436 |
|
$ |
700 |
Research and development |
|
|
132 |
|
|
1,583 |
Total stock-based compensation expense |
|
$ |
568 |
|
$ |
2,283 |
|
| Summary of Warrant Activities |
A summary of warrant activities for years ended December 31, 2023 and 2022, is presented below:
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Weighted Average |
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Remaining |
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|
Weighted Average |
|
Contractual Life (in |
|
|
Warrants |
|
Exercise Price |
|
years) |
Outstanding as of December 31, 2021 |
|
220,577 |
|
$ |
120.30 |
|
0.73 |
Expired |
|
(200,251) |
|
|
127.49 |
|
— |
Granted |
|
49,869 |
|
|
12.03 |
|
9.18 |
Outstanding as of December 31, 2022 |
|
70,195 |
|
$ |
22.80 |
|
8.29 |
Exercised |
|
(93) |
|
|
— |
|
— |
Granted |
|
4,411,766 |
|
|
1.00 |
|
5.29 |
Outstanding as of December 31, 2023 |
|
4,481,868 |
|
$ |
1.34 |
|
5.34 |
|
| Restricted Stock Awards [Member] |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| 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, 2023 and 2022:
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Weighted Average |
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|
|
|
Grant Date Fair |
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|
Number of Shares |
|
Value |
Nonvested at December 31, 2021 |
|
18,732 |
|
$ |
60.75 |
Granted |
|
23,888 |
|
|
10.50 |
Vested |
|
(8,604) |
|
|
73.35 |
Nonvested at December 31, 2022 |
|
34,016 |
|
$ |
22.20 |
Granted |
|
36,230 |
|
|
6.90 |
Vested |
|
(5,540) |
|
|
46.20 |
Nonvested at December 31, 2023 |
|
64,706 |
|
$ |
11.59 |
|
| Restricted Stock Units [Member] |
|
| 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, 2023 and 2022:
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Weighted Average |
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Grant Date Fair |
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|
Number of Units |
|
Value |
Nonvested at December 31, 2021 |
|
155,704 |
|
$ |
49.05 |
Granted |
|
98,976 |
|
|
11.40 |
Forfeited |
|
(34,333) |
|
|
37.95 |
Vested |
|
(54,435) |
|
|
44.70 |
Nonvested at December 31, 2022 |
|
165,912 |
|
$ |
27.60 |
Granted |
|
29,732 |
|
|
5.13 |
Forfeited |
|
(51,366) |
|
|
27.22 |
Vested |
|
(49,081) |
|
|
31.53 |
Nonvested at December 31, 2023 |
|
95,197 |
|
$ |
18.78 |
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