INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2016

INCOME TAXES

Schedule of significant components of net deferred tax assets

	December 31,
	2016		2015
Net operating loss carryforward	$	37,245	$	30,014
Research and development credit carryforward		1,065		942
Stock-based compensation		5,235		3,307
Depreciation and amortization		31		(48)
Accrued expenses		264		186
Charitable contributions		63		96
Subtotal		43,903		34,497
Valuation allowance		(43,903)		(34,497)
Net deferred taxes	$	—	$	—

Schedule of income tax benefits computed using the federal statutory income tax rate

	December 31,
	2016		2015		2014
Statutory rate	(34.0)	%	(34.0)	%	(34.0)	%
State taxes, net of benefit	(5.4)	%	(3.5)	%	(4.8)	%
Permanent differences:
Derivative losses	(0.9)	%	11.0	%	0.7	%
Other	0.2	%	0.3	%	2.6	%
R&D tax credit	(0.5)	%	(0.4)	%	(1.0)	%
Other	0.5	%	0.4	%	2.2	%
Increase in valuation reserve	40.1	%	26.2	%	34.3	%
Effective tax rate	0.0	%	0.0	%	0.0	%