Stock-Based Compensation Expense (Tables)

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-Based Compensation Expense

Stock-based Compensation Expenses

The following tables present the Company's stock-based compensation for equity-settled awards by type (i.e. stock options, restricted stock units ("RSUs"), and rights to purchase shares of common stock under the Company's Employee Stock Purchase Plan ("ESPP")) and financial statement lines included in the accompanying unaudited condensed consolidated statement of operations and comprehensive loss for the three and six months ended June 30:

	Three Months Ended				Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2022		2021		2022		2021
	(in thousands)
Options	$	917	$	413	$	1,800	$	907
RSUs		1,024		—		1,535		—
ESPP		13		—		13		—
Total stock-based compensation expense	$	1,954	$	413	$	3,348	$	907
	Three Months Ended				Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2022		2021		2022		2021
	(in thousands)
Cost of sales	$	140	$	46	$	241	$	107
Selling, general and administrative		1,407		249		2,385	541
Research and development		407		118		722	259
Total stock-based compensation expense	$	1,954	$	413	$	3,348	$	907

Schedule of Unamortized Compensation Cost and Weighted Average Service Period of Unvested Outstanding Awards

Compensation cost related to unvested stock options and RSUs will generally be amortized on a straight-line basis over the remaining average service period. The following table presents the unamortized compensation cost and weighted average service period of all unvested outstanding awards as of June 30, 2022.

	Unamortized Compensation Costs		Weighted Average Service Period
	(in thousands)		(years)
Options	$	8,040		2.8
RSUs		13,961		3.6
Total unamortized compensation cost	$	22,001

Summary of Stock Option Activity under Incentive Plans

The following table summarizes stock option activity under the Company's incentive plans:

	Number of Shares			Weighted Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
						(in years)	(in thousands)
Options outstanding, December 31, 2021		3,119,993		$	7.59
Granted		297,516		$	1.73
Forfeited		(66,588	)	$	9.21
Exercised		(69,556	)	$	3.60		$	140
Options outstanding, June 30, 2022		3,281,365		$	7.10	7.1	$	86
Options vested and exercisable, June 30, 2022		1,685,444		$	5.44	5.6	$	86
Vested and expected to vest after June 30, 2022		3,088,948		$	6.99	7.0	$	86