Condensed Consolidated Statements of Operations (unaudited) - 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	$ 3,745	$ 1,714	$ 6,505	$ 2,894
General and administrative	1,695	1,766	3,707	3,633
Change in fair value of contingent consideration	183	(67)	389	361
Total operating expenses	5,623	3,413	10,601	6,888
Operating loss	(5,623)	(3,413)	(10,601)	(6,888)
Other income (expense)
Cease-use income		3		6
Change in fair value of warrants liabilities	(4,267)	(3,255)	(6,186)	(3,092)
Loss from minority interest investment	(165)		(355)
Interest income	47	30	104	49
Total other income (expense)	(4,385)	(3,222)	(6,437)	(3,037)
Loss from continuing operations	(10,008)	(6,635)	(17,038)	(9,925)
Loss from discontinued operations		(423)		(937)
Net loss	$ (10,008)	$ (7,058)	$ (17,038)	$ (10,862)
Loss per common share from continuing operations, basic and diluted	$ (0.31)	$ (0.33)	$ (0.54)	$ (0.50)
Loss per common share from discontinued operations, basic and diluted		(0.02)		(0.05)
Net loss per common share, basic and diluted	$ (0.31)	$ (0.35)	$ (0.54)	$ (0.55)
Weighted-average common shares outstanding used to calculate basic and diluted net loss per common share	31,776,951	20,345,437	31,766,593	19,940,126