Stock-based compensation (Tables)

9 Months Ended

Sep. 30, 2022

Stock-based compensation

Schedule of assumptions used in the Black-Scholes option-pricing model for estimating the fair value of stock options

	Three months ended September 30,				Nine months ended September 30,
	2022		2021		2022		2021
Risk-free interest rate	—	%	0.94	%	2.87	%	1.06	%
Expected term (in years)	—		6.1		6.0		6.1
Expected volatility	—	%	85.3	%	84.9	%	85.4	%
Expected dividends	—	%	—	%	—	%	—	%

Schedule of summary of stock option activity

The following table summarizes the Company’s stock option activity since January 1, 2022 (in thousands, except share and per share amounts):

				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Shares	Price		Term	Value
				(in years)
Outstanding as of December 31, 2021	4,231,178	$	9.21	7.5	$	1,640
Granted	2,028,531		1.65
Exercised	(34,223)		0.10
Forfeited	(208,489)		9.23
Outstanding as of September 30, 2022	6,016,997	$	6.71	7.7	$	858
Options exercisable as of September 30, 2022	3,043,025	$	8.37	6.5	$	856
Options unvested as of September 30, 2022	2,973,972	$	5.00	9.0	$	2

Schedule of stock-based compensation expense

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

	Three months ended September 30,				Nine months ended September 30,
	2022		2021		2022		2021
Research and development expenses	$	428	$	643	$	1,568	$	2,412
General and administrative expenses		612		1,076		2,474		3,455
	$	1,040	$	1,719	$	4,042	$	5,867