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v3.26.1

Stockholders' Equity (Tables) | 6 Months Ended
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Jun. 30, 2026
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Summary of Stock Option Activity | A summary of the Company’s stock option activity under the Plans is as follows (in thousands, except share, per share data and years):
|  | Number of Options |  |  | Weighted- Average Exercise Price |  |  | Weighted- Average Remaining Contractual Term (in years) |  |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2025 |  |  | 9,547,659 |  |  | $ | 17.97 |  |  |  | 6.7 |  |  | $ | 29,596 |
Granted |  |  | 2,024,970 |  |  | $ | 13.76 |  |  |  |  |  |  |
Exercised |  |  | (505,667 | ) |  | $ | 10.28 |  |  |  |  |  |  |
Forfeited or cancelled |  |  | (1,046,813 | ) |  | $ | 23.90 |  |  |  |  |  |  |
Outstanding at June 30, 2026 |  |  | 10,020,149 |  |  | $ | 16.89 |  |  |  | 6.5 |  |  | $ | 38,573 |
Vested and expected to vest at June 30, 2026 |  |  | 10,020,149 |  |  | $ | 16.89 |  |  |  | 6.5 |  |  | $ | 38,573 |
Exercisable at June 30, 2026 |  |  | 6,855,684 |  |  | $ | 14.60 |  |  |  | 5.4 |  |  | $ | 33,432 |
Summary of Fair Value of Stock Option Grants | The assumptions used in the Black-Scholes option pricing model to determine the fair value of stock options granted under the Plans were as follows:
|  | Six Months Ended June 30,
|  | 2026 |  | 2025
Risk-free interest rate |  | 3.7% – 4.3% |  | 3.9% – 4.4%
Expected volatility |  | 99% – 103% |  | 101% – 104%
Expected term (in years) |  | 5.3 – 6.1 |  | 5.3 – 10.0
Expected dividend yield |  | — |  | —
Summary of Stock-Based Compensation Expense | Stock-based compensation expense has been reported in the condensed statements of operations and comprehensive loss as follows (in thousands):
|  | Three Months Ended June 30, |  |  | Six Months Ended June 30, |
|  | 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
Research and development |  | $ | 3,775 |  |  | $ | 5,489 |  |  | $ | 8,315 |  |  | $ | 10,688 |
General and administrative |  |  | 5,287 |  |  |  | 5,471 |  |  |  | 10,016 |  |  |  | 10,974 |
Total |  | $ | 9,062 |  |  | $ | 10,960 |  |  | $ | 18,331 |  |  | $ | 21,662 |
Summary of Common Stock Reserved for Future Issuance | Common stock reserved for future issuance consists of the following:
|  | June 30, 2026 |  |  | December 31, 2025 |
Common stock options outstanding |  |  | 10,020,149 |  |  |  | 9,547,659 |
RSUs outstanding |  |  | 1,144,335 |  |  |  | 704,869 |
Shares available for issuance under the Plans |  |  | 8,094,201 |  |  |  | 6,630,582 |
Shares available for issuance under the ESPP |  |  | 2,523,465 |  |  |  | 1,969,681 |
Pre-funded common stock warrants outstanding |  |  | 1,901,075 |  |  |  | 1,901,075 |
Total |  |  | 23,683,225 |  |  |  | 20,753,866 |
Two Thousand Twenty One Equity Incentive Plan [Member] |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |
Summary of RSU Activity | A summary of the Company’s RSU activity under the 2021 Plan is as follows:
|  | Number of RSUs |  |  | Weighted- Average Grant Date Fair Value per Share |
Outstanding at December 31, 2025 |  |  | 704,869 |  |  | $ | 48.86 |
Granted |  |  | 841,285 |  |  | $ | 13.81 |
Vested and settled |  |  | (137,972 | ) |  | $ | 53.39 |
Forfeited or cancelled |  |  | (263,847 | ) |  | $ | 29.29 |
Outstanding at June 30, 2026(1) |  |  | 1,144,335 |  |  | $ | 27.06 |
(1) This amount includes 49,146 vested and unsettled RSUs granted to the Company’s non-employee directors who have elected deferred settlement of the RSUs to a specified date following the first to occur of (i) the date that is 30 days following the date of the director's separation from service for any reason, or (ii) a change in control event.

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