Equity Incentive Plans (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

The activity related to equity awards, which are comprised of stock options, during the three months ended March 31, 2021 is summarized as follows:

	Equity Awards			Weighted- average Exercise Price per Share		Weighted- average Remaining Contractual Term⁽¹⁾ (years)		Aggregate Intrinsic Value⁽²⁾
Outstanding at December 31, 2020		4,121,666		$	8.67
Granted		335,548		$	5.48
Exercised		(29,000	)	$	5.25
Cancelled/forfeited		(316,695	)	$	8.00
Outstanding at March 31, 2021		4,111,519		$	8.48		8.39	$	175,807
Exercisable at March 31, 2021		1,146,185		$	17.18		5.68	$	21,693

⁽¹⁾Represents the weighted-average remaining contractual term of stock options.

⁽²⁾ Aggregate intrinsic value represents the product of the number of equity awards outstanding or equity awards exercisable multiplied by the difference between the Company’s closing stock price per share on the last trading day of the period, which was $4.24 as of March 31, 2021, and the exercise price.

Share-based Compensation Expense

The classification of share-based compensation expense is summarized as follows (in thousands):

	Three Months Ended
	March 31,
	2021		2020
Selling, general and administrative	$	840	$	844
Research and development		276		1,563
Total share-based compensation expense	$	1,116	$	2,407