Share-based Compensation Plans (Tables)

9 Months Ended

Sep. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of share-based compensation expense

The following table provides share-based compensation reflected in the Company’s condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2021 and 2020 (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Research and development	$	957	$	1,784	$	2,874	$	5,584
General and administrative		1,455		2,012		4,190		6,200
	$	2,412	$	3,796	$	7,064	$	11,784

Schedule of stock option activity

A summary of stock option activity for the nine months ended September 30, 2021, is as follows:

						Weighted
				Weighted		Average		Average
				Average		Remaining		Intrinsic
	Number			Exercise		Contractual		Value (in
	of Options			Price		Term (Years)		thousands)
Outstanding as of December 31, 2020		7,426,356		$	11.87		7.0		1,178
Granted		834,250			3.40
Exercised		(58,055	)		2.21
Cancelled or forfeited		(1,237,123	)		10.24
Outstanding as of September 30, 2021		6,965,428		$	11.22		6.7	$	873
Exercisable at September 30, 2021		4,373,344		$	13.72		5.7	$	301

Summary of RSU activity

A summary of RSU activity for the nine months ended September 30, 2021 is as follows:

				Weighted Average
	Number			Grant Date
	of Shares			Fair Value
Unvested as of December 31, 2020		294,913		$	14.52
Granted		39,369			3.17
Vested		(88,217	)		15.06
Forfeited		(97,704	)		14.41
Unvested as of September 30, 2021		148,361		$	11.25