Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue (note 9)		$ 132		$ 9,434
Operating expenses:
Research and development	$ 42,880	29,431	$ 126,436	70,937
General and administrative	12,804	8,829	33,923	24,309
Total operating expenses	55,684	38,260	160,359	95,246
Loss from operations	(55,684)	(38,128)	(160,359)	(85,812)
Other income (expense):
Interest income	6,982	3,066	18,929	4,250
Unrealized fair value gain (loss) on trading securities	490	(294)	3,404	(4,944)
Foreign exchange gain (loss)	(407)	(2,381)	289	(2,493)
Other income (expense)	7,065	391	22,622	(3,187)
Loss before income taxes	(48,619)	(37,737)	(137,737)	(88,999)
Income tax recovery	157	587	87	1,021
Net loss	(48,462)	(37,150)	(137,650)	(87,978)
Net loss attributable to preferred shareholders				(420)
Net loss attributable to common shareholders	(48,462)	(37,150)	(137,650)	(87,558)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale securities (note 5)	346	(1,965)	47	(1,965)
Comprehensive loss	$ (48,116)	$ (39,115)	$ (137,603)	$ (89,943)
Net loss per common share (note 3):
Basic	$ (0.73)	$ (0.57)	$ (2.09)	$ (1.49)
Diluted	$ (0.73)	$ (0.57)	$ (2.09)	$ (1.49)
Weighted-average common shares outstanding (note 3):
Basic	66,002,163	65,465,069	65,862,661	58,836,928
Diluted	66,002,163	65,465,069	65,862,661	58,836,928