CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues:
License and contract revenues	$ 0	$ 640
Operating costs and expenses:
Research and development	3,264	5,172
General and administrative	4,467	5,206
Restructuring expenses	0	794
Other operating expenses	4,200	0
Total operating costs and expenses	11,931	11,172
Loss from operations	(11,931)	(10,532)
Non-operating income (expense):
Interest income	119	380
Interest expense	(167)	(294)
Amortization of debt discount and issuance costs	(130)	(130)
Foreign exchange loss	(77)	(238)
Total non-operating expense, net	(255)	(282)
Net loss	$ (12,186)	$ (10,814)
Basic and diluted net loss per common share (in dollars per share)	$ (0.20)	$ (0.19)
Shares used in calculation of basic and diluted net loss per common share (in shares)	62,461	57,973