Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Taxes [Abstract]

Components of Net Deferred Tax Assets

The components of the net deferred tax assets are as follows at December 31:

	2021			2020
	(in thousands)
Operating loss carryforwards	$	54,949		$	46,203
Tax credit carryforwards		3,720			910
Other temporary differences		1,652			5,438
		60,321			52,551
Less valuation allowance		(60,321	)		(52,551	)
Net deferred tax asset	$	—		$	—

Primary Factors Affecting Income Tax Rates

The primary factors affecting the Company’s income tax rates were as follows:

	2021			2020
Tax benefit at U.S. statutory rates		(21	%)		(21	%)
State tax benefit		(4.7	%)		(4.7	%)
Permanent differences		0.5	%		0.8	%
Other		(0.1	%)		(2.2	%)
Changes in valuation allowance		25.3	%		27.1	%
		0	%		0	%