Consolidated Statements of Operations - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statement of Operations [Abstract]
Revenue	$ 28,000	$ 103,000	$ 57,000	$ 209,000
Operating expenses
Research and development expenses	1,130,000	1,241,000	2,620,000	3,221,000
General and administrative	2,784,000	2,451,000	4,682,000	5,095,000
Impairment charges	5,800,000		5,800,000
Total operating expenses	9,714,000	3,692,000	13,102,000	8,316,000
Loss from operations	(9,686,000)	(3,589,000)	(13,045,000)	(8,107,000)
Other income (expense)
Change in fair value of derivative liabilities	1,920,000	(35,000)	2,034,000	1,371,000
Other income, net	3,000		2,000
Other expense, net		(227,000)		(227,000)
Total other income (expense)	1,923,000	(262,000)	2,036,000	1,144,000
Loss before income taxes	(7,763,000)	(3,851,000)	(11,009,000)	(6,963,000)
Income tax benefit	1,302,000		1,302,000
Net loss	(6,461,000)	(3,851,000)	(9,707,000)	(6,963,000)
Excess of fair value of consideration transferred on conversion of Series B redeemable convertible preferred stock		(2,366,000)		(2,366,000)
Accretion of Series B redeemable convertible preferred stock		(133,000)		(1,858,000)
Net loss attributable to common stockholders	$ (6,461,000)	$ (6,350,000)	$ (9,707,000)	$ (11,187,000)
Per share information:
Net loss per share of common stock - basic	$ (1.21)	$ (7.26)	$ (2.76)	$ (15.30)
Weighted average number of shares of common stock outstanding - basic	5,350,930	874,062	3,514,181	731,206
Net loss per share of common stock - diluted	$ (1.46)	$ (7.82)	$ (3.09)	$ (15.96)
Weighted average number of shares of common stock outstanding - diluted	5,519,895	876,806	3,652,501	732,578