CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) shares in Thousands, $ 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	$ 6,613	$ 3,372	$ 19,243	$ 9,406
General and administrative	3,238	3,825	8,910	8,128
Change in fair value of contingent consideration	3,600	7,200	46,600	9,900
Total operating expenses	13,451	14,397	74,753	27,434
Loss from Operations	(13,451)	(14,397)	(74,753)	(27,434)
Other income (expense):
Other income, net	319	382	806	498
Net Loss and Comprehensive Loss	$ (13,132)	$ (14,015)	$ (73,947)	$ (26,936)
Net loss per common share - basic and diluted (in dollars per share)	$ (0.13)	$ (0.18)	$ (0.85)	$ (0.48)
Weighted-average common shares outstanding - basic and diluted (in shares)	101,266	77,030	86,575	56,526

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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