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STOCK-BASED COMPENSATION (Tables) | 9 Months Ended
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Sep. 30, 2022
STOCK-BASED COMPENSATION [Abstract] |
Stock Option Granted | During the three and nine months ended September 30, 2022 and 2021, the Company granted the following stock options (in thousands):
|  | Three months ended September 30, |  |  | Nine months ended September 30, |
|  | 2022 |  |  | 2021 |  |  | 2022 |  |  | 2021 |
Stock options granted |  |  | 188 |  |  |  | 12 |  |  |  | 287 |  |  |  | 180 |
Weighted-Average Assumptions Used for Stock Options Granted | The following weighted-average assumptions were used for stock options granted during the three and nine months ended September 30, 2022 and 2021:
|  | Three months ended September 30, |
|  | 2022 |  |  | 2021 |
Weighted average risk-free rate |  |  | 2.64% |  |  |  | 0.97% |
Weighted average volatility |  |  | 89.80% |  |  |  | 143.29% |
Dividend yield |  |  | 0% |  |  |  | 0% |
Expected term |  | 5.73 years |  |  | 6.08 years |
|  | Nine months ended September 30, |
|  | 2022 |  |  | 2021 |
Weighted average risk-free rate |  |  | 2.54% |  |  |  | 1.06% |
Weighted average volatility |  |  | 91.20% |  |  |  | 134.88% |
Dividend yield |  |  | 0% |  |  |  | 0% |
Expected term |  | 5.30 years |  |  | 6.08 years |
RSU Granted | During the three and nine months ended September 30, 2022 and 2021, the Company granted the following restricted stock units (“RSUs”) (in thousands):
|  | Three months ended September 30, |  |  | Nine months ended September 30, |
|  | 2022 |  |  | 2021 |  |  | 2022 |  |  | 2021 |
RSUs Granted |  |  | - |  |  |  | 6 |  |  |  | 55 |  |  |  | 11 |
RSUs Vested and Settled | The following table shows the number of RSUs that vested and were settled during the three and nine months ended September 30, 2022, as well as the number of shares of common stock withheld to cover the withholding taxes and the net shares issued upon settlement (in thousands):
|  | Three months ended |  |  | Nine months ended |
|  | September 30, 2022 |  |  | September 30, 2022 |
RSUs vested |  |  | 1 |  |  |  | 3 |
Common stock withheld to cover taxes |  |  | - |  |  |  | (1 | )
Common stock issued |  |  | 1 |  |  |  | 2 |
Stock-Based Compensation Expense | For the three and nine months ended September 30, 2022 and 2021, the Company recognized stock-based compensation expense as follows, which includes the expense related to Dr. Federoff’s modified awards discussed above (in thousands):
|  | Three months ended September 30, |  |  | Nine months ended September 30, |
|  | 2022 |  |  | 2021 |  |  | 2022 |  |  | 2021 |
Research and development |  | $ | 183 |  |  | $ | 448 |  |  | $ | 1,075 |  |  | $ | 1,018 |
General and administrative |  |  | 293 |  |  |  | 1,281 |  |  |  | 1,463 |  |  |  | 2,284 |
Total |  | $ | 476 |  |  | $ | 1,729 |  |  | $ | 2,538 |  |  | $ | 3,302 |

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