Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

Summary of Recognized Stock-Based Compensation

The Company recognized stock-based compensation as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
	(In thousands)				(In thousands)
Research and development	$	6,744	$	5,051	$	13,370	$	9,488
General and administrative		5,734		4,027		11,047		8,390
Total stock-based compensation	$	12,478	$	9,078	$	24,417	$	17,878

Summary of Options to Purchase Common Stock

	Number of Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
						(In years)		(In thousands)
Outstanding as of December 31, 2021		11,644,070		$	16.41
Granted		3,069,504			13.56
Exercised		(238,361	)		10.59
Forfeited		(735,800	)		18.86
Outstanding as of June 30, 2022		13,739,413		$	15.74	$	8.2	$	3,814
Exercisable as of June 30, 2022		5,920,555		$	15.07	$	7.3	$	2,258
Vested and expected to vest as of June 30,    2022		13,739,413		$	15.74	$	8.2	$	3,814

Summary of Restricted Stock Awards and Restricted Stock Units

Activity for the RSUs is shown below. In May 2021, the Company began to issue RSUs with market conditions to certain executives, which are included in the table below. The RSUs with market conditions are earned based on stock price performance and continued service by the employee.

	Number of Shares			Weighted Average Grant Date Fair Value per Share
Unvested restricted stock units as of December 31, 2021		1,373,874		$	18.35
Granted		285,922			13.00
Vested		(205,444	)		19.69
Forfeited		(91,151	)		19.58
Unvested restricted stock units as of    June 30, 2022		1,363,201		$	16.94