Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Schedule of Reconciliation between U.S. Federal Statutory Tax Rate and Effective Tax Rate

A reconciliation between the U.S. federal statutory tax rate and the Company’s effective tax rate is summarized as follows:

	For the Years Ended December 31,
	2019			2018
Federal statutory rate		21.0	%		21.0	%
Tax credits		13.4	%		17.7	%
State taxes, net of federal tax benefit		6.1	%		5.5	%
Non-deductible expenses		(1.0	%)		(0.3	%)
Change in valuation allowance		(39.5	%)		(43.9	%)
Effective income tax rate		—	%		—	%

Schedule of Deferred Tax Assets and Liabilities

The principal components of the Company’s deferred tax assets and liabilities consist of the following:

	December 31,
	2019			2018
	(in thousands)
Deferred tax assets:
Net operating losses	$	41,589		$	14,848
R&D credits		25,328			12,506
Deferred revenue		8,456			8,159
Deferred rent		2,966			2,854
Capitalized R&D costs		1,207			1,375
Equity compensation		883			443
Accrued expense and other		108			115
Total deferred tax assets		80,537			40,300
Deferred tax liabilities:
Depreciation		(2,744	)		(2,680	)
Total deferred tax liabilities		(2,744	)		(2,680	)
Valuation allowance		(77,793	)		(37,620	)
Net deferred taxes	$	—		$	—