CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue
Revenue	$ 77,666		$ 203,195
Operating expenses
Cost of revenue	36,634		87,889
Research and development expense	1,239,831	$ 1,126,436	4,414,162	$ 3,275,991
Sales and marketing expense	165,745		519,275
General and administrative expense	1,390,429	1,455,605	3,784,272	3,196,120
Total operating expenses	2,832,639	2,582,041	8,805,598	6,472,111
Loss from operations	(2,754,973)	(2,582,041)	(8,602,403)	(6,472,111)
Interest expense, net	(163,594)	(148,220)	(3,033,238)	(168,384)
Other income	(42,104)		(23,471)
Change in fair value of warrants			(501,617)
Net loss and comprehensive loss	(2,960,671)	(2,730,261)	(12,160,729)	(6,640,495)
Accretion of redeemable convertible preferred stock		(180,832)	(346,374)	(465,841)
Net loss attributable to common stockholders	$ (2,960,671)	$ (2,911,093)	$ (12,507,103)	$ (7,106,336)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.36)	$ (1.01)	$ (2.28)	$ (2.49)
Weighted-average common shares outstanding, basic and diluted (in shares)	8,123,293	2,874,330	5,488,655	2,848,467