Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Consolidated Statement of Operations [Abstract]
Revenue	$ 29,000	$ 143,000	$ 238,000	$ 347,000
Operating expenses
Research and development	1,655,000	728,000	4,876,000	2,777,000
General and administrative	1,781,000	1,843,000	6,876,000	4,857,000
Total operating expenses	3,436,000	2,571,000	11,752,000	7,634,000
Loss from operations	(3,407,000)	(2,428,000)	(11,514,000)	(7,287,000)
Other income (expense)
Change in fair value of warrant liability	1,032,000	7,738,000	2,403,000	9,304,000
Other income		129,000
Other expense			(227,000)	(302,000)
Total other income (expense)	1,032,000	7,867,000	2,176,000	9,002,000
Net (loss) income	(2,375,000)	5,439,000	(9,338,000)	1,715,000
Excess of fair value of consideration transferred on conversion of Series B redeemable convertible preferred stock	(1,214,000)		(3,580,000)
Accretion of Series B redeemable convertible preferred stock		(7,163,000)	(1,858,000)	(9,329,000)
Net (loss) income attributable to common stockholders	$ (3,589,000)	$ (1,724,000)	$ (14,776,000)	$ (7,614,000)
Per share information:
Net loss per share of common stock - basic	$ (0.32)	$ (0.30)	$ (1.72)	$ (1.45)
Weighted average number of shares of common stock outstanding - basic	11,120,394	5,813,063	8,590,772	5,247,508
Net loss per share of common stock - diluted	$ (0.32)	$ (0.30)	$ (1.77)	$ (1.45)
Weighted average number of shares of common stock outstanding - diluted	11,120,394	5,813,063	8,648,914	5,247,508