Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenue (note 10)	$ 2,218	$ 13,384	$ 6,576	$ 20,462
Operating expenses:
Research and development	18,377	10,720	34,685	22,511
General and administrative	6,339	3,310	10,448	6,630
Total operating expenses	24,716	14,030	45,133	29,141
Loss from operations	(22,498)	(646)	(38,557)	(8,679)
Other income (expense):
Interest income	55	912	127	2,028
Interest expense		(154)		(484)
Foreign exchange gain	117	662	272	424
Loss on repayment of term loan (note 8)		(988)		(988)
Loss before income taxes	(22,326)	(214)	(38,158)	(7,699)
Income tax recovery (note 11)	217	39	285	40
Net loss and comprehensive loss	(22,109)	(175)	(37,873)	(7,659)
Net loss attributable to preferred shareholders	(521)	(5)	(951)	(222)
Net loss attributable to common shareholders	$ (21,588)	$ (170)	$ (36,922)	$ (7,437)
Net loss per common share (note 4):
Basic and diluted	$ (0.51)	$ 0.00	$ (0.94)	$ (0.22)
Weighted-average common shares outstanding (note 4):
Basic and diluted	43,106,207	34,979,282	40,473,413	34,084,508