Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating expenses:
Research and development	$ 5,160	$ 4,239	$ 9,357	$ 9,486
General and administrative	2,165	2,397	4,302	4,789
Total operating expenses	7,325	6,636	13,659	14,275
Loss from operations	(7,325)	(6,636)	(13,659)	(14,275)
Other income (expense):
Interest expense		(33)		(90)
Interest and investment income	257	43	483	75
Other (expense) income, net	(63)	147	7	159
Total other income, net	194	157	490	144
Net loss	$ (7,131)	$ (6,479)	$ (13,169)	$ (14,131)
Net loss per share - basic and diluted (in dollars per share)	$ (0.62)	$ (1.98)	$ (1.24)	$ (4.76)
Weighted-average common shares outstanding used in net loss per share - basic and diluted (in shares)	11,505,542	3,272,877	10,600,909	2,965,936

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