Stockholders' Equity (Tables)
|
12 Months Ended |
Dec. 31, 2023 |
|---|
| Stockholders' Equity |
|
| Summary of restricted stock award activity |
|
|
|
|
|
|
|
|
|
|
Weighted Average |
|
|
|
|
Grant Date Fair |
|
|
Number of Shares |
|
Value |
Nonvested at December 31, 2021 |
|
451,266 |
|
$ |
33.48 |
Granted |
|
159,416 |
|
|
20.00 |
Forfeited |
|
(15,850) |
|
|
30.19 |
Vested |
|
(215,935) |
|
|
36.63 |
Nonvested at December 31, 2022 |
|
378,897 |
|
$ |
26.15 |
Granted |
|
1,103,698 |
|
|
2.33 |
Forfeited |
|
(55,100) |
|
|
11.34 |
Vested |
|
(111,375) |
|
|
25.07 |
Non-vested at December 31, 2023 |
|
1,316,120 |
|
$ |
6.88 |
|
| Summary of restricted stock units activity |
|
|
|
|
|
|
|
|
|
|
Weighted Average |
|
|
Number of |
|
Grant Date Fair |
|
|
Shares |
|
Value |
Non-vested at December 31, 2021 |
|
— |
|
$ |
— |
Granted |
|
85,000 |
|
|
10.50 |
Non-vested at December 31, 2022 |
|
85,000 |
|
|
10.50 |
Granted |
|
577,384 |
|
|
2.25 |
Forfeited |
|
(4,000) |
|
|
10.50 |
Vested |
|
(42,500) |
|
|
10.50 |
Non-vested at December 31, 2023 |
|
615,884 |
|
$ |
2.77 |
|
| Summary of stock option award activity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Weighted Average |
|
|
|
|
|
|
|
Remaining |
|
|
|
|
Weighted Average |
|
Contractual Life |
|
|
Stock Options |
|
Exercise Price |
|
(in years) |
Outstanding as of December 31, 2021 |
|
27,000 |
|
$ |
31.35 |
|
7.44 |
Granted |
|
4,000 |
|
|
14.20 |
|
|
Forfeited |
|
(4,000) |
|
|
14.20 |
|
|
Outstanding as of December 31, 2022 |
|
27,000 |
|
$ |
31.35 |
|
6.44 |
Granted |
|
100,000 |
|
|
2.81 |
|
|
Outstanding as of December 31, 2023 |
|
127,000 |
|
$ |
8.88 |
|
8.60 |
Vested and exercisable as of December 31, 2023 |
|
19,500 |
|
$ |
24.68 |
|
6.04 |
|
| Summary of stock options assumptions used |
|
|
|
|
|
|
|
|
For the Years Ended December 31, |
|
|
|
2023 |
|
2022 |
|
Risk-free interest rate |
|
3.7 |
% |
2.9 |
% |
Expected dividend yield |
|
— |
|
— |
|
Expected term in years |
|
10.0 |
|
10.0 |
|
Expected volatility |
|
83.5 |
% |
73.1 |
% |
|
| Summary of warrant activities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Weighted Average |
|
|
|
|
|
|
|
Remaining |
|
|
|
|
Weighted Average |
|
Contractual Life |
|
|
Warrants |
|
Exercise Price |
|
(in years) |
Outstanding as of December 31, 2021 |
|
1,249 |
|
$ |
— |
|
3.83 |
Granted |
|
4,356,361 |
|
|
3.37 |
|
|
Fractional share adjustment |
|
(13) |
|
|
— |
|
|
Outstanding as of December 31, 2022 |
|
4,357,597 |
|
$ |
3.37 |
|
3.26 |
Granted |
|
35,513,575 |
|
|
2.30 |
|
|
Exercised |
|
(9,773,501) |
|
|
1.76 |
|
|
Outstanding as of December 31, 2023 |
|
30,097,671 |
|
$ |
2.36 |
|
3.00 |
|
| Summary of stock-based compensation expense |
The following table summarizes stock-based compensation expense for the years ended December 31, 2023 and 2022 (in thousands).
|
|
|
|
|
|
|
|
|
For the year ended December 31, |
|
|
2023 |
|
2022 |
Research and development |
|
$ |
1,169 |
|
$ |
888 |
General and administrative |
|
|
1,728 |
|
|
2,036 |
Total stock-based compensation expense |
|
$ |
2,897 |
|
$ |
2,924 |
|