STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Expenses:
Research and development	$ 2,817	$ 7,258	$ 6,390	$ 12,752
General and administrative	1,691	1,586	3,503	3,190
Loss from operations	(4,508)	(8,844)	(9,893)	(15,942)
Interest income	31	34	71	56
Interest expense	(72)	(124)	(156)	(248)
Other expense	(3)	(15)	(12)	(31)
Net loss	$ (4,552)	$ (8,949)	$ (9,990)	$ (16,165)
Per share information:
Net loss per share of common stock-basic and diluted (in dollars per share)	$ (0.21)	$ (0.46)	$ (0.47)	$ (0.83)
Basic and diluted weighted average shares outstanding (in shares)	21,985,213	19,509,220	21,288,545	19,486,944