Consolidated and combined statements of cash flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net loss	$ (21,860)	$ (24,027)	$ (8,729)
Non-cash items and reclassifications:
Financing costs		320	14
Fees and penalty on bank loan repayment		100
Amortization and extinguishment of remaining discount on preferred stock upon conversion of preferred stock		1,884	386
Change in fair value of derivative liabilities	52	(949)	(962)
Stock-based compensation (Note 8(d))	1,506	854	349
Stock-based purchase of patent rights		186
Foreign exchange loss and others	580	549	41
Changes in operating assets and liabilities:
Accounts and other amounts receivable	34	(37)
Prepayments and deposits	(130)	20	(102)
Accounts payable and other liabilities	(450)	3,614	1,180
Cash used in operating activities	(20,268)	(17,486)	(7,823)
Investing activities
Purchase of investments	(60,703)	(36,475)	(2,821)
Proceeds from maturity of investments	13,196	12,990
Purchase of property and equipment	(27)	(114)	(11)
Sale of property and equipment	1	26	192
Cash used in investing activities	(47,533)	(23,573)	(2,640)
Financing activities
Bank loan (repayment) and receipt, fees and penalty		(2,600)	2,392
Preferred stock issued			18,003
Share issue costs			(224)
Proceeds from exercise of stock options	1,120
Public offering of common shares	98,038	53,130
Public offering costs	(6,210)	(5,251)	(587)
Cash provided by financing activities	92,948	45,279	19,584
Effect of exchange rate changes on cash and cash equivalents	(527)	(320)	(116)
Increase in cash and cash equivalents during the period	24,620	3,900	9,005
Cash and cash equivalents, beginning of period	14,906	11,006	2,001
Cash and cash equivalents, end of period	39,526	14,906	11,006
Supplemental disclosure of cash flow information:
Interest paid		32	23
Interest received	108	$ 91	26
Non-cash investing and financing activities:
Assets acquired through non-capital leases	11
Accrued offering costs	$ 35		$ 790