Stock-Based Compensation (Tables)

6 Months Ended

Jun. 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	1,062,318		7.56
Cancelled / Forfeited	(240,548)		6.26
Exercised	(119,131)		0.62
Balance as of June 30, 2022	3,452,080	$	8.18		$	4,095
Options exercisable as of June 30, 2022	1,417,978	$	5.50		$	3,435

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				Six months ended
	June 30,				June 30,
(in thousands)	2022		2021		2022		2021
Stock options	$	998	$	624	$	1,791	$	685
Employee Stock Purchase Plan		102		—		102		—
Total stock-based compensation expense	$	1,100	$	624	$	1,893	$	685
Selling, general & administrative	$	943	$	431	$	1,617	$	477
Research & development		133		190		235		204
Cost of goods sold		24		3		41		4
	$	1,100	$	624	$	1,893	$	685

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 six months ended June 30, 2022:

	June 30,
		2022
Weighted average fair value per ESPP purchase right	$	1.76
Expected term (in years)		0.5
Expected volatility		51.3	%
Expected dividend yield		—	%
Risk-free interest rate		0.22	%

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 six months ended June 30, 2022:

	June 30,
		2022			2021
Weighted average fair value of options granted	$	4.41		$	5.16
Expected term (in years) — non-officer employees		5.5 to 6.1			2.7
Expected term (in years) — officer employees		3.2 to 6.1			3.0
Expected volatility		56.3% to 58.6	%		61.6 to 63.4	%
Expected dividend yield		—	%		—	%
Risk-free interest rate		1.75% to 3.07	%		0.17% to 0.47	%