Equity Incentive Plan (Tables)

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

Summary of Total Stock-based Compensation Including Both Stock Option Awards and Restricted Stock

Total stock-based compensation was classified as follows on the unaudited interim condensed consolidated statements of operations (in thousands):

	THREE MONTHS ENDED JUNE 30,				SIX MONTHS ENDED JUNE 30,
	2022		2021		2022		2021
General and administrative	$	1,476	$	1,029	$	2,738	$	1,768
Research and development		704		627		1,422		1,060
Total stock-based compensation	$	2,180	$	1,656	$	4,160	$	2,828

Summary of Option Activity

A summary of option activity for the six months ended June 30, 2022 is presented below:

	SHARES			WEIGHTED AVERAGE EXERCISE PRICE		WEIGHTED- AVERAGE REMAINING CONTRACTUAL TERM (YEARS)		AGGREGATE INTRINSIC VALUE (IN THOUSANDS)
Outstanding at December 31, 2021		3,681,793		$	10.84
Granted		1,723,500		$	1.75
Exercised		(34,863	)	$	1.77
Canceled, expired or forfeited		(181,652	)	$	8.34
Outstanding at June 30, 2022		5,188,778		$	7.97		8.29	$	33
Vested and expected to vest at June 30, 2022		5,188,778		$	7.97		8.29	$	33
Exercisable at June 30, 2022		1,670,042		$	7.73		6.98	$	25