Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Taxes

Schedule of income (loss) before income taxes

	Year Ended
	December 31,
	2019		2018
U.S.	$	(32,875)	$	(21,378)
Foreign		(28)		(1,740)
Loss before income taxes	$	(32,903)	$	(23,118)

Schedule of Company's current and deferred expense for income tax

	Year Ended
	December 31,
	2019		2018
Current expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		—		—
Total current expense (benefit):	$	—	$	—
Deferred expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		(3)		20
Total deferred expense (benefit):	$	(3)	$	20
Total income tax expense (benefit):	$	(3)	$	20

Schedule of reconciliation of the Company's statutory income tax rate to the Company's effective income tax rate

	Year Ended
	December 31,
	2019		2018
Federal statutory income tax rate	21.00	%	21.00	%
State taxes, net of federal benefit	6.79	%	7.76	%
Permanent differences	(0.33)	%	2.38	%
Tax credits	3.30	%	6.94	%
Foreign rate differential	0.07	%	0.68	%
Valuation allowance	(40.18)	%	(38.26)	%
Other	9.35	%	(0.59)	%
	0.01	%	(0.09)	%

Schedule of significant components of the Company's deferred tax assets

	Year Ended
	December 30,
	2019		2018
Federal net operating loss carryforwards	$	47,845	$	38,531
State net operating loss carryforwards		7,431		5,553
Stock Options		2,584		1,632
Federal research tax credits		3,770		2,811
State research tax credits		510		382
License fees		1,332		1,495
Accrued expenses		277		88
Other		115		149
Total deferred tax assets	$	63,864	$	50,641
Valuation allowance		(63,737)		(50,517)
Net deferred tax asset (liability)	$	127	$	124