Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2022

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

A summary of stock option activity during the three months ended March 31, 2022 is as follows:

	Number of Units Outstanding			Weighted Average Strike Price per Unit		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021		8,590,411		$	5.48		8.8	$	6,196
Granted		256,800		$	1.89
Exercised		(65,862	)	$	1.50
Forfeited		(697,607	)	$	6.67
Expired		(161,468	)	$	3.43
Outstanding at March 31, 2022		7,922,274		$	5.33		8.6	$	—
Exercisable at March 31, 2022		2,753,490		$	5.28		8.4	$	—
Nonvested at March 31, 2022		5,168,784		$	5.36		8.8	$	—

As of March 31, 2022, the total unrecognized stock-based compensation related to stock options, excluding the stock option granted to Brian Coe, a former Chief Executive Officer of the Company with the performance condition (discussed further below), was $16.6 million, which is expected be recognized over a weighted-average period of approximately 3 years.

During 2020, Mr. Coe received stock options for the purchase of 241,958 shares of common stock that vest upon the first sale by the Company of a regulatory authorized product. As of March 31, 2022, there was $1.8 million of unrecognized compensation expense related to these stock options as the achievement of the performance condition was not deemed probable.

Summary of Restricted Stock Unit Activity

A summary of RSU activity during the three months ended March 31, 2022 is as follows:

	Number of Units Outstanding			Weighted Average Grant Date Fair Value (per RSU)
Outstanding at December 31, 2021		407,720		$	5.72
Granted		41,300		$	2.53
Vested		—		$	—
Forfeited		(80,905	)	$	5.86
Outstanding at March 31, 2022		368,115		$	5.35

Components of Stock-based Compensation Expense

The following table summarizes the components of stock-based compensation expense recorded in the Company’s statement of operations and comprehensive loss (in thousands):

	Three Months Ended March 31,
	2022		2021
Research and development	$	575	$	623
Selling, general and administrative		970		1,149
Total stock-based compensation	$	1,545	$	1,772