Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating expenses:
Research and development	$ 6,857	$ 11,753
General and administrative	2,799	3,064
Total operating expenses	9,656	14,817
Loss from operations	(9,656)	(14,817)
Other income:
Interest income	60	10
Other income (expense), net	7	49
Total other income	67	59
Net loss	$ (9,589)	$ (14,758)
Net loss per share, basic and diluted (usd per share)	$ (0.31)	$ (0.62)
Weighted-average common shares outstanding, basic and diluted (in shares)	30,563,088	23,972,599