Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues:
Product sales				$ 7
Grant revenue	961	66	1,142	325
Total revenues	961	66	1,142	332
Expenses:
Cost of product sales				929
Research and development	7,081	6,452	25,757	20,663
Selling, general and administrative	1,613	2,057	7,053	8,793
Total expenses	8,694	8,509	32,810	30,385
Operating loss	(7,733)	(8,443)	(31,668)	(30,053)
Change in fair value of common stock warrant liability		139	223	577
Other income / (expense):
Loss on debt extinguishment		(11,758)		(11,758)
Interest income	3	1	15	2
Interest expense	(648)	(1,495)	(1,907)	(3,962)
Other income	15		449	133
Other expense, net	(630)	(13,252)	(1,443)	(15,585)
Net loss	$ (8,363)	$ (21,556)	$ (32,888)	$ (45,061)
Net loss per common share – Basic and diluted (in dollars per share)	$ (1)	$ (2.80)	$ (3.98)	$ (6.86)
Weighted-average number of common shares outstanding – basic and diluted (in shares)	8,355	7,550	8,262	6,601