CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue	$ 0	$ 37
Operating expenses
Research and development	4,603	5,480
General and administrative	3,379	3,523
Impairment of technology license	608	0
Total operating expenses	8,590	9,003
Net operating loss	(8,590)	(8,966)
Other income (loss)
Change in fair value of warrant liability	0	2,374
Loss on extinguishment of warrant liability	0	(440)
Interest income	7	9
Total other income	7	1,943
Net loss	(8,583)	(7,023)
Deemed dividend related to warrant conversion	0	(1,038)
Net loss attributable to common stockholders	$ (8,583)	$ (8,061)
Net loss per share, basic and diluted	$ (14.38)	$ (15.99)
Basic and diluted weighted average number of common shares outstanding	597	504