Consolidated Statements of Operations and Comprehensive Loss (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	$ 8,205	$ 5,416	$ 17,342	$ 10,984
General and administrative	2,307	2,178	4,928	4,416
Total operating expenses	10,512	7,594	22,270	15,400
Loss from operations	(10,512)	(7,594)	(22,270)	(15,400)
Other income (expense):
Interest income	706	125	1,388	233
Interest expense	(365)	(200)	(723)	(359)
Foreign exchange gain (loss)	135	(140)	265	(424)
Gain on termination of collaboration agreement (note 9c)				4,398
Loss before income taxes	(10,036)	(7,809)	(21,340)	(11,552)
Income tax (expense) recovery (note 10)	29	8	(8)	(4)
Net loss and comprehensive loss	(10,007)	(7,801)	(21,348)	(11,556)
Net loss attributable to preferred shareholders	(380)	(1,303)	(810)	(996)
Net loss attributable to common shareholders	$ (9,627)	$ (6,498)	$ (20,538)	$ (10,560)
Net loss per common share (note 4):
Basic and diluted	$ (0.37)	$ (0.45)	$ (0.80)	$ (0.66)
Weighted-average common shares outstanding (note 4):
Basic	25,773,879	14,306,491	25,763,858	16,055,456
Diluted	25,775,559	14,306,491	25,763,858	16,055,456