Condensed consolidated statements of cash flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating activities
Net loss	$ (11,162)	$ (9,653)
Non-cash items and reclassifications:
Financing costs		320
Fees and penalty on bank loan repayment		100
Amortization and extinguishment of remaining discount on preferred stock upon conversion of preferred stock		1,884
Change in fair value of derivative liabilities	(6)	(928)
Stock-based compensation	721	352
Stock-based purchase of patent rights		186
Foreign exchange loss and others	26	196
Changes in operating assets and liabilities:
Accounts and other amounts receivable	(7)	(5)
Prepayments and deposits	(438)	(268)
Accounts payable and accrued liabilities	(1,232)	1,207
Cash used in operating activities	(12,098)	(6,609)
Investing activities
Purchase of investments	0	(34,475)
Proceeds from maturity of investments	12,094	2,714
Purchase of property and equipment	(6)	(69)
Cash (used in) provided by investing activities	12,088	(31,830)
Financing activities
Bank loan repayment, fees and penalty		(2,600)
Proceeds from exercise of stock options	96
Public offering of common shares		53,130
Public offering costs	(76)	(5,201)
Cash (used in) provided by financing activities	20	45,329
Increase (decrease) in cash and cash equivalents during the period	10	6,890
Cash and cash equivalents, beginning of period	14,906	11,006
Cash and cash equivalents, end of period	14,916	17,896
Supplemental disclosure of cash flow information:
Interest paid		32
Interest received	27	50
Non-cash financing activities:
Accrued offering costs	$ 11	$ 50