Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating expenses:
Research and development	$ 4,697	$ 3,897	$ 14,054	$ 13,383
General and administrative	1,985	2,111	6,287	6,900
Total operating expenses	6,682	6,008	20,341	20,283
Loss from operations	(6,682)	(6,008)	(20,341)	(20,283)
Other income (expense):
Interest expense		(10)		(100)
Interest and investment income	214	177	697	252
Other (expense) income, net	(46)	162	(39)	321
Total other income, net	168	329	658	473
Net loss	$ (6,514)	$ (5,679)	$ (19,683)	$ (19,810)
Net loss per share - basic and diluted (in dollars per share)	$ (0.56)	$ (0.80)	$ (1.80)	$ (4.54)
Weighted-average common shares outstanding used in net loss per share - basic and diluted (in shares)	11,624,232	7,103,842	10,945,765	4,360,395

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