Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

Total stock-based compensation expense recognized was as follows (in thousands):

	Three Months Ended March 31,
	2023		2022
Research and development	$	2,207	$	1,687
General and administrative		2,558		2,663
Total stock-based compensation	$	4,765	$	4,350

Summary of Stock Option Activity

Stock Options

A summary of stock option activity for the three months ended March 31, 2023 is set forth below:

	Number of Shares Underlying Outstanding Options			Weighted Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2022		6,203,020		$	14.44		8.4	$	780
Options granted		2,117,400		$	8.06
Options exercised		(713	)	$	4.76
Options forfeited or cancelled		(178,112	)	$	12.82
Outstanding, March 31, 2023		8,141,595		$	12.82		8.6	$	143
Options exercisable, March 31, 2023		2,671,676		$	14.15		7.8	$	143
Vested and expected to vest, March 31, 2023		8,141,595		$	12.82		8.6	$	143

Schedule of Assumptions to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model

The assumptions used in the Black Scholes Model to calculate stock-based compensation are as follows:

	Three Months Ended March 31,
	2023	2022
Fair value of common stock	$5.76 - $9.15	$11.93 - $19.97
Expected term (years)	6.0 - 6.1	5.8 - 6.1
Volatility	83.25% - 86.19%	77.4% - 77.7%
Risk free rates	3.55% - 4.22%	1.6% - 2.4%
Dividend rate	0.0%	0.0%

Summary of Restricted Stock Unit Activity

The summary of RSU activity and related information for the nine months ended March 31, 2023 is set forth below:

	Number of Units Outstanding			Weighted Average Grant Date Fair Value
Outstanding, December 31, 2022		197,580		$	7.8
RSUs granted		472,400		$	7.8
RSUs vested		(3,205	)	$	17.2
RSUs forfeited		(19,675	)	$	7.4
Outstanding, March 31, 2023		647,100		$	7.8