Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Schedule of Stock Option Activity

The following is a summary of stock option activity:

		Weighted
	Number	Average		Aggregate
	of	Exercise		Intrinsic
	Options	Price		Value
				(in  thousands)
Balance as of December 31, 2021	2,749,441	$	7.93
Granted	1,406,783		7.87
Cancelled / Forfeited	(310,780)		7.56
Exercised	(121,945)		0.67
Balance as of September 30, 2022	3,723,499	$	8.17		$	10,623
Options exercisable as of September 30, 2022	1,547,838	$	5.96		$	7,581

Recognized Stock-Based Compensation Expense

The following table presents the components and classification of stock-based compensation expense for the periods indicated:

	Three Months Ended				Nine months ended
	September 30,				September 30,
(in thousands)	2022		2021		2022		2021
Stock options	$	866	$	474	$	2,657	$	1,159
Employee Stock Purchase Plan		63		—		165		—
Total stock-based compensation expense	$	929	$	474	$	2,822	$	1,159
Selling, general & administrative	$	785	$	353	$	2,402	$	830
Research & development		132		115		367		319
Cost of goods sold		12		6		53		10
	$	929	$	474	$	2,822	$	1,159

ESPP

Schedule of Assumptions Used to Determine the Grant-Date Fair Value of Stock Options

The following table provides the weighted average fair value of ESPP purchase rights and the related assumptions used in the Black-Scholes option pricing model for the nine months ended September 30, 2022:

	September 30,
		2022
Weighted average fair value per ESPP purchase right	$	2.85
Expected term (in years)		0.5
Expected volatility		51.3% to 62.9	%
Expected dividend yield		—	%
Risk-free interest rate		0.22% to 2.52	%

Stock options

Schedule of Assumptions Used to Determine the Grant-Date Fair Value of Stock Options

The following table provides the weighted average fair value of options granted to employees and the related assumptions used in the Black-Scholes option pricing model for the nine months ended September 30, 2022 and 2021:

	September 30,
		2022			2021
Weighted average fair value of options granted	$	4.56		$	5.25
Expected term (in years) — non-officer employees		5.5 to 6.1			2.7 to 6.1
Expected term (in years) — officer employees		3.2 to 6.1			3.0
Expected volatility		56.3% to 58.6	%		56.1% to 63.4	%
Expected dividend yield		—	%		—	%
Risk-free interest rate		1.75% to 3.97	%		0.17% to 0.47	%