CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating expenses:
Research and development	$ 2,280	$ 1,381	$ 4,144	$ 3,240
General and administrative	1,987	2,638	4,187	5,138
Total operating expenses and operating loss	(4,267)	(4,019)	(8,331)	(8,378)
Non-operating (expense) income, net:
Change in fair value of warrant liability	(16)	962	19	1,157
Change in fair value of contingent consideration	(143)	(95)	(281)	(482)
Interest income, net	1	18	25	32
Total non-operating (expense) income, net	(158)	885	(237)	707
Net loss	(4,425)	(3,134)	(8,568)	(7,671)
Deemed dividend arising from warrant modifications	0	(952)	(78)	(1,391)
Net loss attributable to common stockholders	$ (4,425)	$ (4,086)	$ (8,646)	$ (9,062)
Per share information:
Net loss per common share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.66)	$ (6.33)	$ (1.32)	$ (16.56)
Weighted-average common shares outstanding, basic and diluted (in shares)	6,717,900	645,965	6,546,440	547,212