Condensed consolidated statements of cash flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities
Net loss	$ (8,316)	$ (6,711)
Non-cash items and reclassifications:
Change in fair value of derivative liability (Note 6)		(50)
Stock-based compensation (Note 5(c))	631	433
Unrealized foreign exchange loss and others	146	31
Changes in operating assets and liabilities:
Receivable, prepayments and deposits	(426)	(465)
Accounts payable and other liabilities	(3,315)	890
Cash used in operating activities	(11,280)	(5,872)
Investing activities
Purchase of investments		(13,002)
Proceeds from maturity of investments		15,025
Purchase of property and equipment	(108)	(27)
Cash (used in) provided by investing activities	(108)	1,996
Financing activity
Payment on capital lease obligations	(4)
Cash used in financing activity	(4)
Effect of exchange rate changes on cash and cash equivalents	7	41
Net change in cash and cash equivalents during the period	(11,385)	(3,835)
Cash and cash equivalents, beginning of period	32,301	39,526
Cash and cash equivalents, end of period	20,916	35,691
Supplemental disclosure of cash flow information:
Interest received	234	$ 121
Non-cash investing and financing activities:
Accrued purchase of property & equipment	$ (24)