Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Taxes

Summary of loss before income taxes

Loss before income taxes is allocated as follows (in thousands):

	Year Ended December 31,
	2021		2020
U.S. operations	$	98,776	$	67,475
Foreign operations		—		—
Loss before income taxes	$	98,776	$	67,475

Schedule of components of the net deferred tax asset

The components of the net deferred tax asset are as follows (in thousands):

	December 31,
	2021		2020
Gross deferred tax assets:
Net operating loss carryforwards	$	81,719	$	59,819
Accrued expenses		272		219
Amortization of intangible		251		—
Stock‑based compensation		5,944		4,270
Research and development and other credits and other carryforwards		16,216		11,906
Lease liability		610		879
Capitalized research and development expenses		11,437		15,891
Unrealized income		—		12
Other		9		4
Total gross deferred tax assets	$	116,458	$	93,000
Gross deferred tax liabilities:
ROU Asset		(399)		(569)
Depreciation		(99)		(252)
Unrealized income		(212)		—
Total gross deferred tax liabilities		(710)		(821)
Net deferred tax assets		115,748		92,179
Less: valuation allowance		(115,748)		(92,179)
Net deferred tax assets after valuation allowance	$	—	$	—

Schedule of reconciliation of income tax expense (benefit) at the statutory federal income tax rate and income taxes

	Year Ended December 31,
	2021		2020
Federal income tax expense at statutory rate	21.0	%	21.0	%
Permanent items	(0.7)		(0.7)
State income tax, net of federal benefit	2.2		7.6
R&D tax credits	4.3		4.7
Change in state tax rate	(2.8)		—
Foreign income tax effect	—		—
Capitalized research and development expenses	—		26.2
Other	—		—
Change in valuation allowance	(24.0)		(58.8)
Effective income tax rate	0.0	%	0.0	%