Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Schedule of Income (loss) Before Income Taxes

Income Before Taxes

The domestic and foreign components of (loss) profit before income taxes were as follows (in thousands):

	Fiscal Year Ended
	December 31, 2020			December 28, 2019
United States	$	(28,803	)	$	(33,668	)
Foreign		87			161
	$	(28,716	)	$	(33,507	)

Reconciliation of U.S. Federal Statutory Income Tax Rate to Company's Effective Income Tax Rate

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows:

	Fiscal Year Ended
	December 31, 2020			December 28, 2019
Federal statutory income tax rate		(21.0	)%		(21.0	)%
State taxes, net of federal benefit		(5.7	)%		(6.2	)%
Federal and state research and development tax credits		(3.6	)%		(2.8	)%
Nondeductible items		(0.2	)%		0.2	%
Deferred tax effect of change in state blended rate		7.8	%		0.0	%
Return to provision		1.7	%		0.0	%
Other		0.0	%		0.9	%
Change in deferred tax asset valuation allowance		20.9	%		29.0	%
Effective income tax rate		(0.1	)%		0.1	%

Schedule of Net deferred Tax Assets

Net deferred tax assets consisted of the following (in thousands):

	December 31, 2020			December 28, 2019
Deferred tax assets:
Net operating loss carryforwards	$	81,390		$	74,206
Capitalized research and development expense		6,136			8,505
Research and development tax credit carryforwards		11,541			10,745
Accrued expenses		1,390			1,309
Stock-based compensation expense		791			243
Deferred rent		79			157
Other		132			—
Total deferred tax assets		101,459			95,165
Deferred tax liabilities:
Other		(218	)		(141	)
Unrealized gain (loss)		(212	)		—
Total deferred tax liabilities		(430	)		(141	)
Valuation allowance		(101,029	)		(95,024	)
Net deferred tax assets	$	—		$	—

Summary Changes in the Valuation Allowance for Deferred Tax Assets

Changes in the valuation allowance for deferred tax assets during the fiscal years ended December 31, 2020 and December 28, 2019 related primarily to the increase in net operating loss carryforwards and research and development tax credit carryforwards in 2020 and 2019, and were as follows (in thousands):

	Fiscal Year Ended
	December 31, 2020			December 28, 2019
Valuation allowance as of beginning of year	$	(95,024	)	$	(85,316	)
Decreases recorded as benefit to income tax provision		—			—
Increases recorded to income tax provision		(6,005	)		(9,708	)
Valuation allowance as of end of year	$	(101,029	)	$	(95,024	)