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Share-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedule of Share-based Compensation Expense | Share-based compensation expense by type of award was as follows (in thousands):
| Year Ended December 31, |
| 2024 |  | 2023 |  | 2022 |
Stock options | $ | 28,057 |  | $ | 20,661 |  | $ | 14,859 |
Restricted stock units |  | 27,257 |  |  | 12,254 |  |  | 4,056 |
Restricted stock units - chief executive officer |  | 5,266 |  |  | 8,336 |  |  | 2,548 |
ESPP |  | 506 |  |  | 538 |  |  | 81 |
Total share-based compensation expense | $ | 61,086 |  | $ | 41,789 |  | $ | 21,544 |
Share-based compensation expense as reflected in the consolidated statement of operations and comprehensive loss was as follows (in thousands):
| Year Ended December 31, |
| 2024 |  | 2023 |  | 2022 |
Research and development | $ | 21,359 |  | $ | 11,003 |  | $ | 7,007 |
General and administrative |  | 39,727 |  |  | 30,786 |  |  | 14,537 |
Total share-based compensation expense | $ | 61,086 |  | $ | 41,789 |  | $ | 21,544 |
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, 2024 |  | 7,811,231 |  | $ | 12.46 |  |  | 7.8 |  | $ | 336,174 |
Options Granted |  | 1,031,954 |  |  | 56.22 |  |  |  |  |
Options Forfeited |  | (145,261 | ) |  | 11.10 |  |  |  |  |
Options Exercised |  | (1,457,826 | ) |  | 9.75 |  |  |  |  |
Outstanding as of December 31, 2024 |  | 7,240,098 |  | $ | 19.28 |  |  | 6.9 |  | $ | 415,634 |
Exercisable as of December 31, 2024 |  | 4,712,405 |  | $ | 13.30 |  |  | 6.6 |  | $ | 298,737 |
(1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair value of the common stock for those options for which the exercise price was below the market price as of December 31, 2024.
Schedule of Assumptions used in Black-Scholes Option Pricing Model for Stock Options Granted | The assumptions used in the Black-Scholes option pricing model for stock options granted for the years ending December 31, 2024, 2023 and 2022 were as follows:
|  | 2024 |  | 2023 |  | 2022
Expected term |  | 5.5 - 6.27 years |  | 5.5 - 6.25 years |  | 6.0 - 6.3 years
Expected volatility |  | 86% - 87% |  | 75% - 80% |  | 68% - 75%
Risk free interest rate |  | 3.82% - 4.56% |  | 3.92% - 4.06% |  | 1.56% - 3.88%
Expected dividend yield |  | — % |  | — % |  | — %
Summary of Restricted Stock Units Activity | A summary of RSU activity for awards under the 2022 Plan, excluding the 2023 RSU Award and 2021 RSU Award (each defined below) granted to the chief executive officer, is presented below:
| Shares Subject to Outstanding Awards |  | Weighted Average Grant Date Fair Value |
Outstanding as of January 1, 2024 |  | 1,416,446 |  | $ | 25.47 |
RSUs Granted |  | 981,531 |  |  | 61.66 |
RSUs Vested |  | (528,711 | ) |  | 23.76 |
RSUs Forfeited |  | (57,421 | ) |  | 32.55 |
Outstanding as of December 31, 2024 |  | 1,811,845 |  | $ | 45.35 |
January 2023 RSU Grant |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedule of Assumptions used in Determining Fair Value for Stock Options and RSU Awards |
|  | Semi-Annual Measurement |  |  | Change in Control |
Time to award end date |  | 10 years |  |  | 5 years |
Equity volatility |  | 75% |  |  | 75% |
Risk-free interest rate |  | 3.8% |  |  | 3.9% |
Fair value of the 2023 RSU award (in thousands) |  | $ | 13,811 |  |  | $ | 10,999 |
June and December 2021 RSU Grant |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Schedule of Assumptions used in Determining Fair Value for Stock Options and RSU Awards | The assumptions used in the Monte Carlos simulation models to determine the grant date fair value of the 2021 RSU Award for each of the three performance condition scenarios were as follows:
|  | Change in Control |  |  | IPO |  |  | Change in Control Following an IPO |
Date of grant |  | June 9, 2021 |  |  | December 7, 2021 |  |  | December 7, 2021 |
Time to liquidity event (years) |  | 1.56 - 3.06 |  |  |  | 10.00 |  |  | 1.33 |
Equity volatility |  | 100% - 110% |  |  | 70% |  |  | 65% |
Risk-free interest rate |  | 0.1% - 0.3% |  |  | 1.5% |  |  | 0.4% |
Discount for lack of marketability |  | 26% - 32% |  |  | 5% |  |  | 5% |
Fair value of the 2021 RSU award (in thousands) |  | $ | 1,580 |  |  | $ | 10,300 |  |  | $ | 150 |

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