Stockholders' Equity (Tables)
|
6 Months Ended |
Jun. 30, 2022 |
|---|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Summary of Stock Option Activities |
The following table summarizes stock option activities for the six months ended June 30, 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 |
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Exercise Price |
|
years) |
Outstanding at December 31, 2021 |
|
1,141,675 |
|
$ |
5.73 |
|
5.31 |
Outstanding at June 30, 2022 |
|
1,141,675 |
|
|
5.73 |
|
4.81 |
Options vested and exercisable at June 30, 2022 |
|
713,547 |
|
$ |
5.73 |
|
4.81 |
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| Schedule of Stock-Based Compensation Expense |
The following table summarizes stock-based compensation expense for the three and six months ended June 30, 2022 and 2021 (in thousands):
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For the three months ended June 30, |
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For the six months ended June 30, |
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|
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2022 |
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2021 |
|
2022 |
|
2021 |
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General and administrative |
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$ |
208 |
|
$ |
240 |
|
$ |
355 |
|
$ |
564 |
|
Research and development |
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|
442 |
|
|
307 |
|
|
959 |
|
|
979 |
|
Total stock-based compensation expense |
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$ |
650 |
|
$ |
547 |
|
$ |
1,314 |
|
$ |
1,543 |
|
|
| Summary of Warrant Activities |
A summary of warrant activities for the six months ended June 30, 2022, is presented below:
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Weighted Average |
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Remaining |
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|
Weighted Average |
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Contractual Life (in |
|
|
Warrants |
|
Exercise Price |
|
years) |
Outstanding as of December 31, 2021 |
|
3,308,654 |
|
$ |
8.02 |
|
0.73 |
Expired |
|
(3,000,270) |
|
|
8.50 |
|
— |
Granted |
|
748,036 |
|
|
0.80 |
|
9.68 |
Outstanding as of June 30, 2022 |
|
1,056,420 |
|
$ |
1.54 |
|
8.76 |
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| 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 |
The following table summarizes restricted stock award activities for the six months ended June 30, 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 |
|
280,983 |
|
$ |
4.05 |
Vested |
|
(129,058) |
|
|
4.89 |
Nonvested at June 30, 2022 |
|
151,925 |
|
$ |
3.33 |
|
| Restricted Stock Units [Member] |
|
| 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 consultants have been awarded restricted stock units with time-based vesting. The following table summarizes restricted stock units’ activities for the six months ended June 30, 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 |
|
2,335,557 |
|
$ |
3.27 |
Granted |
|
870,000 |
|
|
0.91 |
Forfeited |
|
(276,686) |
|
|
2.83 |
Vested |
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(455,562) |
|
|
3.43 |
Nonvested at June 30, 2022 |
|
2,473,309 |
|
$ |
2.27 |
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