Stock-Based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Summary of Stock Option Activities

A summary of the stock option activities related to the Equity Plans for the three months ended March 31, 2024 is presented below:

	Number of Options			Weighted Average Exercise Price		Weighted Avg Remaining Contractual Life (Years)
Options outstanding as of December 31, 2023		6,777,404		$	13.02		6.51
Granted		787,102			55.86
Exercised		(941,617	)		10.78
Forfeited		(56,806	)		14.19
Expired		(9,680	)		4.13
Options outstanding as of March 31, 2024		6,556,403			18.48		6.90
Exercisable as of March 31, 2024		3,615,132		$	12.23		5.36

Summary of Non-Vested Restricted stock unit Activities

A summary of non-vested restricted stock unit activities for the three months ended March 31, 2024 is as follows:

				Weighted
				Average
	Number of			Grant Date
	Shares			Fair Value
Unvested at December 31, 2023		650,357		$	15.80
Granted		162,799			56.07
Vested		(119,719	)		14.86
Forfeited		(16,485	)		15.14
Unvested at March 31, 2024		676,952		$	25.67

Schedule of Stock-Based Compensation Expense

Stock-based compensation expense was classified in the accompanying condensed consolidated statements of operations and comprehensive income (loss) as follows (in thousands):

	Three Months Ended March 31,
	2024		2023
Research and development	$	1,106	$	802
Selling, general and administrative		3,199		2,272
Cost of sales		391		221
	$	4,696	$	3,295

Schedule of Range and Weighted-average Assumptions Used in Black-Scholes Option Pricing Model to Determine the Fair Value of Stock Options

The following table presents the range and weighted-average assumptions, used in the Black-Scholes option pricing model to determine the fair value of stock options:

	Three Months Ended March 31,
	2024		2023
	Range	Weighted Average	Range	Weighted Average
Expected volatility	70.7% to 72.3%	71.0%	64.9% to 65.2%	65.1%
Risk-free interest rate	3.9% to 4.3%	4.2%	3.4% to 4.2%	4.1%
Expected life (in years)	6.0 years	6.0 years	6.0 to 10.0 years	6.0 years
Expected dividend yield	0.0%	0.0%	0.0%	0.0%
Grant date fair value	$36.89 to $56.07	$55.89	$12.91 to $16.68	$14.86

Schedule of Common stock reserved for future issuance

Each share of common stock is entitled to one vote. Common stock reserved for future issuance consisted of the following:

	March 31, 2024		December 31, 2023
Stock options issued and outstanding under the Equity Plans		6,556,403		6,777,404
Shares available for future issuance under the 2021 Plan		976,356		358,610
Restricted stock units issued under the 2021 Plan		676,952		650,357
Shares available for future issuance under 2021 ESPP		577,847		577,847
Total shares of common stock reserved		8,787,558		8,364,218