Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenue (note 13):	$ 32,166	$ 6,829
Operating expenses:
Research and development	50,523	38,845
General and administrative	12,944	10,803
Total operating expenses	63,467	49,648
Loss from operations	(31,301)	(42,819)
Other income (expense):
Interest income	2,283	2,353
Interest expense	(484)	(1,434)
Foreign exchange gain	1,396	282
Loss on repayment of term loan (note 10)	(988)
Loss before income taxes	(29,094)	(41,618)
Income tax recovery (note 15)	(257)	(23)
Net loss and comprehensive loss	(28,837)	(41,595)
Net loss attributable to preferred shareholders	(824)	(1,568)
Net loss attributable to common shareholders	$ (28,013)	$ (40,027)
Net loss per common share (note 6):
Basic and diluted	$ (0.81)	$ (1.54)
Weighted-average common shares outstanding (note 6):
Basic and diluted	34,542,213	25,939,405