Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Components of Income Tax (Provision) Benefit

The provision (benefit) for income taxes charged to operations was as follows:

	2022		2021
	(in thousands)
Current tax expense
U.S. federal	$	—	$	—
State and local		2		2
Total current		2		2
Deferred tax expense:
U.S. federal	$	—	$	—
State and local		—		—
Total deferred		—		—
Total provision for income taxes	$	2	$	2

Schedule of Effective Tax Rate of Provision (Benefit) for Income Taxes

A reconciliation of the provision for income taxes with the expected income tax computed by applying the statutory federal income tax rate to loss before provision for income taxes and a reconciliation of the statutory federal rate and the effective rate was calculated as follows:

	Year Ended December 31,
	2022			2021
Tax computed at federal statutory rate		21.00	%		21.00	%
State income tax - net of federal benefit		2.01	%		3.31	%
Tax credits		0.98	%		1.13	%
Change in valuation allowance		(20.41	)%		(25.51	)%
Stock-based compensation		(2.03	)%		(0.20	)%
Other deferred adjustments		(1.31	)%		0.56	%
Permanent items		(0.24	)%		(0.29	)%
Income tax provision		0.00	%		0.00	%

Significant Components of Net Deferred Taxes

The significant components that comprised the Company’s net deferred taxes at December 31, 2022 and 2021 are as follows:

	2022			2021
	(in thousands)
Deferred tax assets:
Net operating loss carryforwards	$	78,276		$	70,731
Fixed assets and intangible assets		1,244			1,449
Lease liabilities		514			660
Accruals and reserves		1,170			1,178
Stock-based compensation		918			864
Tax credits		5,375			4,763
State Taxes		-			3
Employee Retention Credit		172			-
Research & Development		3,077			-
Other		1,346			890
Gross deferred tax assets		92,092			80,538
Less: valuation allowance		(91,113	)		(79,476	)
Net deferred tax assets		979			1,062
Deferred tax liabilities:
Fixed assets and intangible assets		(408	)		(392	)
Right-of-use assets		(571	)		(670	)
State Taxes		—			—
Total gross deferred tax liabilities:		(979	)		(1,062	)
Net deferred tax asset (liability)	$	—		$	—

Summary of Changes in Unrecognized Tax Benefits

The following changes occurred in the amount of unrecognized tax benefits:

	2022		2021
	(in thousands)
Gross unrecognized tax benefits at the beginning of the year	$	1,791	$	1,575
Increases related to current year tax positions		207		204
Increases related to prior year tax positions		22		12
Gross unrecognized tax benefits at the end of the year	$	2,020	$	1,791