Equity Incentive Plans (Tables)

3 Months Ended

Mar. 31, 2022

The following table summarizes stock option activity during the three months ended March 31, 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	4,041,165	$	11.86
Options exercised	(39,525)	$	3.18
Options forfeited/cancelled	(114,608)	$	15.49
Outstanding as of March 31, 2022	13,321,692	$	12.13	7.9	$	7,047
Options vested and expected to vest as of March 31, 2022	13,321,692	$	12.13	7.9	$	7,047
Options exercisable as of March 31, 2022	5,549,308	$	12.40	6.5	$	6,670

The summary of the Company’s restricted stock activity during the three months ended March 31, 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	(684,252)	9.23
Forfeited	(34,664)	10.43
Nonvested at March 31, 2022	2,415,204	$	9.27

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


	Three months ended March 31,
	2022		2021
Research and development	$	6,618	$	5,442
General and administrative	4,365		3,266
Total stock-based compensation expense	$	10,983	$	8,708