Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating activities:
Net loss	$ (11,556)	$ (14,897)
Items not involving cash:
Depreciation	302	334
Amortization of discount on term loan	164
Stock-based compensation	1,363	1,076
Unrealized foreign exchange (gain) loss	406	(819)
Gain on termination of collaboration agreement (note 9c)	(4,398)
Changes in operating assets and liabilities:
Accounts receivable	263	5
Prepaid expenses, and other current assets	(193)	590
Prepaid expenses, long term	230	123
Accounts payable and accrued expenses	(338)	326
Net cash used in operating activities	(13,757)	(13,262)
Investing activities:
Purchases of property, plant and equipment	(318)	(238)
Purchase of marketable securities	(17,911)	(22,281)
Proceeds from marketable securities	25,146	41,099
Net cash provided by investing activities	6,917	18,580
Financing activities:
Proceeds from issuance of second tranche under term loan, net of issuance costs (note 8)	4,989
Issuance of common shares, net of issuance costs (note 9a)	28,957
Issuance of common shares pursuant to exercise of stock options	182	177
Net cash provided by financing activities	34,128	177
Effect of exchange rate changes on cash and cash equivalents	(339)	500
Increase in cash and cash equivalents	26,949	5,995
Cash and cash equivalents, beginning of period	20,486	17,095
Cash and cash equivalents, end of period	47,435	23,090
Supplemental disclosures:
Interest paid	164
Interest received	289	457
Supplemental disclosures of non-cash transactions:
Fair value of stock options exercised on a cashless basis	212	$ 25
Issuance of preferred shares in exchange for common shares (note 9b)	21,825
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 9c)	$ 4,470