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Share-Based Compensation (Tables)

12 Months Ended

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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-Name Accounting Standards Codification
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