CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating expenses:
Research and development	$ 24,366	$ 21,830
General and administrative	9,085	8,921
Total operating expenses	33,451	30,751
Loss from operations	(33,451)	(30,751)
Interest income	313	447
Interest expense	(23)	(19)
Australian research and development incentives	132	756
Foreign currency gains (loss)	126	(835)
Change in fair value of warrant liability		7,284
Loss before income taxes	(32,903)	(23,118)
Income taxes	3	(20)
Net loss	(32,900)	(23,138)
Dividend attributable to down round feature of warrants	(359)
Net loss attributable to common stockholders	$ (33,259)	$ (23,138)
Net loss per share
Basic (in dollars per share)	$ (1.47)	$ (1.64)
Diluted (in dollars per share)	$ (1.47)	$ (2.11)
Weighted average common shares outstanding
Basic (in shares)	22,582,687	14,144,287
Diluted (in shares)	22,582,687	14,412,695