Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues:
Product sales	$ 28	$ 0
Grant revenue	3	72
Total revenues	31	72
Expenses:
Cost of product sales	781	0
Research and development	5,590	8,472
Selling, general and administrative	4,423	4,220
Total expenses	10,794	12,692
Operating loss	(10,763)	(12,620)
Change in fair value of common stock warrant liability	378	162
Other income / (expense):
Interest and other income	2	1
Interest and other expense	(1,093)	(178)
Other income / (expense), net	(1,091)	(177)
Net loss	$ (11,476)	$ (12,635)
Net loss per common share - Basic and diluted (in dollars per share)	$ (0.14)	$ (0.29)
Weighted average number of common shares outstanding - basic and diluted (in shares)	84,728	43,657