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Share-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2022
Share-Based Payment Arrangement [Abstract] |
Summary of Stock Option Activity | The following table summarizes the stock option activity during the year ended December 31, 2022 (in thousands, except number of shares, exercise prices and contractual term):
|  | Number of shares |  |  | Weighted-average exercise price |  |  | Weighted-average remaining contractual term (in years) |  |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2021 |  |  | 4,204,686 |  |  | $ | 19.19 |  |  |  | 8.2 |  |  |  |
Granted |  |  | 2,327,820 |  |  |  | 12.61 |  |  |  |  |  |  |
Exercised |  |  | (383,120 | ) |  |  | 3.62 |  |  |  |  |  |  |
Forfeited |  |  | (630,111 | ) |  |  | 21.99 |  |  |  |  |  |  |
Outstanding at December 31, 2022 |  |  | 5,519,275 |  |  | $ | 17.17 |  |  |  | 8.1 |  |  | $ | 2,915 |
Exercisable at December 31, 2022 |  |  | 2,337,753 |  |  | $ | 17.49 |  |  |  | 7.4 |  |  | $ | 1,957 |
Vested and expected to vest at December 31, 2022 |  |  | 5,519,275 |  |  | $ | 17.17 |  |  |  | 8.1 |  |  | $ | 2,915 |
Summary of Additional Information Related to Stock Options | Additional information related to the Company’s stock options is summarized below (in thousands, except per share amounts):
|  | Year Ended December 31, |
|  | 2022 |  |  | 2021 |
Weighted-average grant-date fair value of stock option grants per share |  | $ | 8.60 |  |  | $ | 30.87 |
Intrinsic value of options exercised |  | $ | 4,268 |  |  | $ | 9,991 |
Summary of Restricted Stock Unit Activity | The following table summarizes the restricted stock unit activity during the year ended December 31, 2022:
|  | Number of shares |  |  | Weighted-average grant date fair value per share |  |  | Weighted- average remaining contractual term (in years) |
Outstanding at December 31, 2021 |  |  | — |  |  | $ | — |  |  |  |
Granted |  |  | 389,388 |  |  |  | 12.62 |  |  |  |
Forfeited |  |  | (32,660 | ) |  |  | 12.15 |  |  |  |
Vested |  |  | — |  |  |  | — |  |  |  |
Outstanding at December 31, 2022 |  |  | 356,728 |  |  | $ | 12.66 |  |  |  | 1.7 |
Summary of Common Stock Reserved For Future Issuance | As of December 31, 2022, the Company had reserved the following shares of common stock for future issuance:
|  | December 31, 2022 |
Common stock options and restricted stock units granted and outstanding |  |  | 5,876,003 |
Reserved for future equity award grants |  |  | 1,775,102 |
Reserved for future ESPP issuances |  |  | 890,770 |
|  |  | 8,541,875 |
Summary of Share-based Compensation Expense | Share-based compensation expense for the years ended December 31, 2022 and 2021 were as follows (in thousands):
|  | Year Ended December 31, |
|  | 2022 |  |  | 2021 |
Research and development |  | $ | 7,326 |  |  | $ | 6,719 |
General and administrative |  |  | 9,530 |  |  |  | 7,742 |
Total share-based compensation expense |  | $ | 16,856 |  |  | $ | 14,461 |
Schedule of Fair Value of Stock Options Estimated on Date of Grant Using Black-Scholes Option Pricing Model | The fair value of stock options was estimated on the date of grant using the Black-Scholes option pricing model with the following range of assumptions:
|  | Year Ended December 31,
|  | 2022 |  | 2021
Options |  |  |  |
Common stock fair value |  | $5.99 - $18.44 |  | $15.35 - $54.89
Risk-free interest rate |  | 1.6% - 4.2% |  | 0.6% - 1.4%
Expected volatility |  | 75.7% - 78.9% |  | 77.3% - 79.9%
Expected term (in years) |  | 5.5 - 6.1 |  | 5.5 - 6.1
Expected dividend yield |  | — |  | —
ESPP |  |  |  |
Risk-free interest rate |  | 1.6% - 4.7% |  | —
Expected volatility |  | 63.8% - 151.9% |  | —
Expected term (in years) |  | 0.5 |  | —
Expected dividend yield |  | — |  | —

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- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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