Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenues	$ 45		$ 45
Operating expenses:
Research and development	5,088	$ 7,330	20,715	$ 21,106
Selling, general and administrative	2,134	2,460	7,408	8,448
Depreciation and amortization	24	38	86	105
Total operating expenses	7,246	9,828	28,209	29,659
Loss from operations	(7,201)	(9,828)	(28,164)	(29,659)
Interest income	31	32	107	94
Interest expense	(948)	(101)	(1,979)	(102)
Other income (loss), net	(34)	(15)	(29)	(12)
Net loss	$ (8,152)	$ (9,912)	$ (30,065)	$ (29,679)
Net loss per share - basic and diluted	$ (0.04)	$ (0.06)	$ (0.15)	$ (0.18)
Weighted average shares outstanding - basic and diluted	214,714,029	163,614,297	196,527,686	161,748,944
Comprehensive Income/(Loss):
Net loss	$ (8,152)	$ (9,912)	$ (30,065)	$ (29,679)
Other comprehensive income/(loss)	(3)	(1)	22	34
Comprehensive net loss	$ (8,155)	$ (9,913)	$ (30,043)	$ (29,645)