Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
License and milestone fees	$ 1,710	$ 302	$ 9,637
Collaborative revenue	2,093	2,201	2,225
Clinical compound revenue	0	674	102
Total revenue	3,803	3,177	11,964
Operating expenses:
Research and development	21,221	15,068	8,685
General and administrative	7,770	6,181	3,516
Total operating expenses	28,991	21,249	12,201
Operating loss	(25,188)	(18,072)	(237)
Other income (expense), net	101	126	(3,756)
Loss before benefit from income taxes	(25,087)	(17,946)	(3,993)
Benefit from income taxes	397	201	30
Net loss	(24,690)	(17,745)	(3,963)
Net loss available to common stockholders:
Basic and Diluted	$ (24,690)	$ (17,745)	$ (3,072)
Loss per share available to common stockholders:
Basic and Diluted	$ (1.00)	$ (0.85)	$ (0.74)
Weighted average shares:
Basic and Diluted	24,620,372	20,965,935	4,133,138
Other comprehensive loss, net of tax of $0:
Unrealized gains (losses) on available for sale marketable securities	$ (35)
Total comprehensive loss	$ (24,725)	$ (17,745)	$ (3,072)