Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net loss	$ (41,595)	$ (34,497)
Items not involving cash:
Depreciation	429	586
Amortization of discount on term loan	525	284
Deferred income tax recovery	(133)	(105)
Stock-based compensation	2,924	2,625
Unrealized foreign exchange (gain) loss	(302)	646
Gain on termination of collaboration agreement (note 13c)		(4,398)
Changes in operating assets and liabilities:
Accounts receivable	(653)	280
Prepaid expenses and other current assets	(820)	(928)
Accounts payable and accrued expenses	4,541	783
Deferred revenue	30,452
Net cash used in operating activities	(4,632)	(34,724)
Investing activities:
Purchases of property, plant and equipment	(1,240)	(507)
Purchase of marketable securities	(140,494)	(77,002)
Proceeds from marketable securities	75,443	48,522
Net cash used in investing activities	(66,291)	(28,987)
Financing activities:
Proceeds from issuance of refinanced term loan, net of issuance costs (note 10)		8,453
Issuance of common shares, net of issuance costs (note 11a)	27,396	102,850
Issuance of common shares pursuant to exercise of stock options	122	288
Net cash provided by financing activities	27,518	111,591
Effect of exchange rate changes on cash and cash equivalents	406	(612)
Increase (decrease) in cash and cash equivalents	(42,999)	47,268
Cash and cash equivalents, beginning of year	67,754	20,486
Cash and cash equivalents, end of year	24,755	67,754
Supplemental disclosures:
Interest paid	917	561
Interest received	2,216	1,067
Cash paid for operating lease	634	624
Supplemental disclosures of non-cash transactions:
Fair value of stock options and warrants exercised on a cashless basis	$ 719	1,125
Issuance of preferred shares in exchange for common shares (note 11d)		21,825
Conversion of preferred shares to common shares (note 11d)		14,093
Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member]
Supplemental disclosures of non-cash transactions:
Termination of Teva agreement through cancellation of common shares (note 13c)		$ 4,470