Equity Incentive Plans (Tables)

9 Months Ended

Sep. 30, 2022

Share-based Payment Arrangement [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity during the nine months ended September 30, 2022:

	Shares Subject to Options Outstanding			Weighted- Average
	Shares	Weighted- Average Exercise Price		Remaining Contractual Life (Years)	Aggregate Intrinsic Value
					(in thousands)
Outstanding as of December 31, 2021	9,434,660	$	12.24	7.4	$	15,822
Options granted	4,447,720	$	11.50
Options exercised	(269,103)	$	6.40
Options forfeited/cancelled	(823,901)	$	15.77
Outstanding as of September 30, 2022	12,789,376	$	11.89	7.6	$	19,765
Options vested and expected to vest as of September 30, 2022	12,789,376	$	11.89	7.6	$	19,765
Options exercisable as of September 30, 2022	6,115,757	$	12.17	6.4	$	14,169

Summary of Restricted Stock Activity

The summary of the Company’s restricted stock activity during the nine months ended September 30, 2022 is as follows:

	Number of Restricted Stock Units Outstanding	Weighted- Average Grant Date Fair Value
Nonvested at December 31, 2021	2,561,219	$	8.67
Granted	572,901	11.94
Vested	(1,087,210)	7.72
Forfeited	(190,222)	10.67
Nonvested at September 30, 2022	1,856,688	$	10.04

Stock-Based Compensation Expense Reported in Condensed Consolidated Statements of Operations

Stock-based compensation expense has been reported in the Company’s condensed consolidated statements of operations and comprehensive loss as follows (in thousands):

	Three months ended September 30,				Nine months ended September 30,
	2022		2021		2022		2021
Research and development	$	5,595	$	4,349	$	17,800	$	14,435
General and administrative	4,527		3,238		13,304		9,914
Total stock-based compensation expense	$	10,122	$	7,587	$	31,104	$	24,349