Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation

The effective income tax rate of the provision for income taxes differs from the federal statutory rate as follows:

	Year Ended December 31,
	2023			2022
Federal statutory income tax rate		21	%		21	%
State income taxes, net of federal benefit		1			5
Research and developments credits		1			1
Permanent items		(3	)		(4	)
Change in valuation allowance		(20	)		(23	)
Effective income tax rate		—	%		—	%

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences that give rise to significant portions of the deferred income tax assets and liabilities are as follows (in thousands):

	As of December 31,
	2023			2022
Deferred Tax Assets:
Net operating loss carryforwards	$	72,722		$	70,822
Research and development tax credits		4,149			3,807
Interest expense limitation		5,120			3,036
Property and equipment		—			234
Capitalized research costs		4,281			2,874
Share-based compensation		1,685			1,619
Lease liability		6,398			—
Accruals and reserves		667			1,932
Total		95,022			84,324
Valuation allowance		(93,023	)		(82,552	)
Total deferred tax assets after valuation allowance		1,999			1,772
Deferred Tax Liabilities:
Property and equipment		(4	)		—
Right-of-Use Asset		(692	)		—
Intangible assets		(1,303	)		(1,772	)
Total deferred tax liabilities		(1,999	)		(1,772	)
Net deferred tax assets and liabilities	$	—		$	—

Reconciliation of Unrecognized Tax Benefits

A reconciliation of beginning and ending balances for unrecognized tax benefits is as follows (in thousands):

	Year Ended December 31,
	2023		2022
Balance at January 1	$	952	$	843
Additions for tax positions related to the current year		57		109
Additions for tax positions related to prior years		28		—
Reductions for tax positions related to prior years		—		—
Reductions related to settlements		—		—
Reductions related to a lapse of statute		—		—
Balance at December 31	$	1,037	$	952