Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Operating expenses:
Research and development	$ 3,294	$ 2,432	$ 8,659	$ 7,280
General and administrative	2,584	3,437	8,573	9,861
Total operating expenses	5,878	5,869	17,232	17,141
Operating loss	(5,878)	(5,869)	(17,232)	(17,141)
Other income (expense):
Interest income	50	2	133	6
Interest expense	(32)	(32)	(117)	(97)
Derivatives (loss) gain	(336)	3,591	(788)	(11,349)
Other income (expense), net	(318)	3,561	(772)	(11,440)
Net loss	$ (6,196)	$ (2,308)	$ (18,004)	$ (28,581)
Net loss per share, basic and diluted (in dollars per share)	$ (0.19)	$ (0.09)	$ (0.59)	$ (1.09)
Weighted average number of common shares outstanding, basic and diluted	31,968,357	27,010,444	30,687,263	26,150,525