Income taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of Income Tax Recovery

Income tax recovery varies from the amounts that would be computed by applying the expected U.S. federal income tax rate (21%) as shown in the following table:

	December 31,
	2022		2021
Statutory federal income tax rate	(21.0)	%	(21.0)	%
Stock-based compensation	2.2		2.0
Change in valuation allowance	21.4		21.2
Tax credits	(2.6)		(2.2)
Income tax recovery	—	%	—	%

Schedule of Net (Loss) Income Before Taxes

Net loss before taxes (in thousands):	Years Ended December 31,
	2022		2021
U.S.	(57,578)		(60,692)
Total	$	(57,578)	$	(60,692)

Components of Deferred Income Tax Assets

The significant components of the deferred income tax assets are as follows (in thousands):

	December 31,
	2022		2021
Deferred tax assets:
U.S. net operating losses	$	26,362	$	22,863
Research and development deductions and credits	3,931		2,414
Intangibles	446		457
Lease liability	2,456		2,701
Stock-based compensation	2,274		1,695
Capitalized research and development	6,920		—
Other	168		186
Total deferred tax assets:	42,557		30,316
Deferred income tax liabilities
Right-of-use assets	2,040		2,261
Other	410		287
Total deferred tax liabilities	2,450		2,548
Net deferred income tax assets	40,107		27,768
Less: valuation allowance	(40,107)		(27,768)
Deferred tax assets, net of valuation allowance	$	—	$	—