CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Operating expenses:
Research and development	$ 4,686	$ 3,255
General and administrative	3,055	1,952
Gain from change in fair value of contingent consideration	(1,000)	(1,200)
Total operating expenses	6,741	4,007
Loss from operations	(6,741)	(4,007)
Other income:
Other income, net	261	44
Total other income, net	261	44
Net loss and comprehensive loss	$ (6,480)	$ (3,963)
Net loss per share — basic and diluted (in dollars per share)	$ (0.08)	$ (0.11)
Weighted-average number of common shares used in net loss per share- basic and diluted (in shares)	77,458	35,674

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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