Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Fair Value of Stock Option Awards on the Grant Date Using the Black-Scholes Option Valuation Model

The following table presents, on a weighted-average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted:

	YEAR ENDED DECEMBER 31,
	2022			2021
Fair value of common stock	$	5.72		$	15.55
Expected term (years)		6.0			6.0
Expected volatility		77.0	%		76.4	%
Risk-free interest rate		2.22	%		0.90	%
Expected annual dividend yield		0	%		0	%

Summary of Stock Option Activity

The following table summarizes the Company’s stock option activity since December 31, 2021:

	NUMBER OF SHARES			WEIGHTED- AVERAGE EXERCISE PRICE		WEIGHTED- AVERAGE REMAINING CONTRACTUAL TERM		INTRINSIC VALUE
						(in years)		(in thousands)
Outstanding at December 31, 2021		4,339,523		$	9.75		7.68	$	8,823
Granted		2,563,920			5.72
Exercised		(14,757	)		1.95
Forfeited or canceled		(1,530,376	)		8.89
Outstanding at December 31, 2022		5,358,310		$	8.09		5.26	$	—
Vested and expected to vest at December 31, 2022		5,358,310		$	8.09		5.26	$	—
Options exercisable at December 31, 2022		2,628,431		$	8.43		3.81	$	—

Summary of Stock-Based Compensation Expense

Stock-based compensation expense related to stock options and restricted stock awards was classified in the consolidated statements of operations as follows (in thousands):

	YEAR ENDED DECEMBER 31,
	2022		2021
Research and development expenses	$	3,293	$	3,243
General and administrative expenses		4,729		5,262
Restructuring charges		381		—
	$	8,403	$	8,505