Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Revenue (note 9)		$ 536		$ 9,302
Operating expenses:
Research and development	$ 44,040	22,146	$ 83,556	41,506
General and administrative	11,584	8,705	21,119	15,480
Total operating expenses	55,624	30,851	104,675	56,986
Loss from operations	(55,624)	(30,315)	(104,675)	(47,684)
Other income (expense):
Interest income	6,524	816	11,947	1,184
Unrealized fair value gain (loss) on trading securities	1,036	(1,288)	2,914	(4,650)
Foreign exchange gain (loss)	383	(411)	696	(112)
Other income (expense)	7,943	(883)	15,557	(3,578)
Loss before income taxes	(47,681)	(31,198)	(89,118)	(51,262)
Income tax recovery (expense)	220	40	(70)	434
Net loss	(47,461)	(31,158)	(89,188)	(50,828)
Net loss attributable to preferred shareholders				(385)
Net loss attributable to common shareholders	(47,461)	(31,158)	(89,188)	(50,443)
Other comprehensive loss:
Unrealized loss on available-for-sale securities (note 5)	(1,479)		(299)
Comprehensive loss	$ (48,940)	$ (31,158)	$ (89,487)	$ (50,443)
Net loss per common share (note 3):
Basic	$ (0.72)	$ (0.55)	$ (1.36)	$ (0.91)
Diluted	$ (0.72)	$ (0.55)	$ (1.36)	$ (0.91)
Weighted-average common shares outstanding (note 3):
Basic	65,861,138	56,192,922	65,792,910	55,522,857
Diluted	65,861,138	56,192,922	65,792,910	55,522,857