Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (19,670)	$ (15,764)
Items not involving cash:
Depreciation	376	196
Deferred income tax recovery	258	9
Stock-based compensation	3,614	1,965
Unrealized foreign exchange gain	(142)	(204)
Unrealized fair value loss on marketable securities	3,362	74
Changes in operating assets and liabilities:
Accounts receivable	(155)	(3,238)
Prepaid expenses and other current assets	(272)	(533)
Accounts payable and accrued expenses	(5,799)	(3,213)
Net cash used in operating activities	(18,428)	(20,708)
Investing activities:
Purchases of property, plant and equipment	(212)	(404)
Purchases of marketable securities	(68,956)	(100,655)
Proceeds from marketable securities	20,280	45,955
Net cash used in investing activities	(48,888)	(55,104)
Financing activities:
Issuance of common shares and pre-funded warrants, net of issuance costs (note 7a)	7,876	118,615
Issuance of common shares pursuant to exercise of stock options		106
Net cash provided by financing activities	7,876	118,721
Effect of exchange rate changes on cash and cash equivalents	293	67
Increase (decrease) in cash and cash equivalents	(59,147)	42,976
Cash and cash equivalents, beginning of period	175,688	45,009
Cash and cash equivalents, end of period	116,541	87,985
Supplemental disclosures:
Interest received	1,682	651
Cash paid for operating lease	203	202
Supplemental disclosures of non-cash transactions:
Fair value of stock options exercised on a cashless basis	$ 1,529	$ 448