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Share-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2023
Share-Based Payment Arrangement [Abstract] |
Schedule of Share-based Compensation Expense | Share-based compensation expense by type of award was as follows (in thousands):
| March 31 |
| 2023 |  | 2022 |
Stock options | $ | 4,915 |  | $ | 3,030 |
Restricted stock units |  | 2,877 |  |  | 696 |
Restricted stock units - chief executive officer |  | 2,206 |  |  | 755 |
ESPP |  | 158 |  | — |
Total share-based compensation expense | $ | 10,156 |  | $ | 4,481 |
Share-based compensation expense as reflected in the condensed consolidated statement of operations and comprehensive loss was as follows (in thousands):
| March 31 |
| 2023 |  | 2022 |
Research and development | $ | 2,691 |  | $ | 1,284 |
General and administrative |  | 7,465 |  |  | 3,197 |
Total share-based compensation expense | $ | 10,156 |  | $ | 4,481 |
Summary of Stock Option Activity | A summary of stock option activity for awards under the 2017 Plan and the 2022 Plan is presented below:
| Options Outstanding and Exercisable |
| Shares Subject to Outstanding Options |  | Weighted Average Exercise Price per Option |  | Weighted Average Remaining Contractual Life Term (in Years) |  | Aggregate Intrinsic Value (1) (in thousands) |
Outstanding as of January 1, 2023 |  | 8,053,704 |  | $ | 9.59 |  |  | 8.3 |  | $ | 172,294 |
Options Granted |  | 821,604 |  |  | 31.03 |  |  |  |  |
Options Forfeited |  | — |  |  | — |  |  |  |  |
Options Exercised |  | (34,713 | ) |  | 10.78 |  |  |  |  |
Outstanding as of March 31, 2023 |  | 8,840,595 |  | $ | 11.58 |  |  | 8.2 |  | $ | 170,230 |
Exercisable as of March 31, 2023 |  | 3,706,377 |  | $ | 7.36 |  |  | 7.3 |  | $ | 86,935 |
(1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money as of March 31, 2023.
Summary of Restricted Stock Units Activity | A summary of RSU activity for awards under the 2022 Plan, excluding those granted the chief executive officer below, is presented below:
| Shares Subject to Outstanding Awards |  | Weighted Average Grant Date Fair Value |
Outstanding as of January 1, 2023 |  | 927,954 |  | $ | 17.20 |
RSUs Granted |  | 745,660 |  |  | 31.25 |
RSUs Vested |  | (222,433 | ) |  | 18 |
RSUs Forfeited |  | (6,800 | ) |  | 22.81 |
Outstanding as of March 31, 2023 |  | 1,444,381 |  | $ | 24.33 |
Schedule of Assumptions used in Determining Grant Date Fair Value of RSU Awards |
|  | Semi-Annual Measurement |  |  | Change in Control |
Time to award end date |  | 10 years |  |  | 5 years |
Equity volatility |  | 75.0% |  |  | 75.0% |
Risk-free interest rate |  | 3.8% |  |  | 3.9% |
Fair value of the 2023 RSU award (in thousands) |  | $ | 13,811 |  |  | $ | 10,999 |

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