Statements of Operations and Comprehensive Income (Loss) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenue:
Collaboration revenue (note 9)	$ 4,010us-gaap_LicensesRevenue	$ 5,001us-gaap_LicensesRevenue
Operating expenses:
Research and development	3,427us-gaap_ResearchAndDevelopmentExpense	2,533us-gaap_ResearchAndDevelopmentExpense
General and administrative	1,789us-gaap_GeneralAndAdministrativeExpense	1,436us-gaap_GeneralAndAdministrativeExpense
Total operating expenses	5,216us-gaap_OperatingExpenses	3,969us-gaap_OperatingExpenses
Income (loss) from operations	(1,206)us-gaap_OperatingIncomeLoss	1,032us-gaap_OperatingIncomeLoss
Other income (expense):
Interest income	152us-gaap_InvestmentIncomeInterest	141us-gaap_InvestmentIncomeInterest
Foreign exchange gain (loss)	(3,171)	200
Net income (loss)	(4,225)us-gaap_NetIncomeLoss	1,373us-gaap_NetIncomeLoss
Net income attributable to participating securities		1,373
Net loss attributable to common shareholders	(4,225)
Net loss per common share:
Basic and diluted	$ (0.30)us-gaap_EarningsPerShareBasicAndDiluted
Weighted-average shares outstanding:
Basic and diluted	14,212,579	1,345,312
Other comprehensive income (loss):
Foreign currency translation adjustment		(909)
Comprehensive income (loss)	$ (4,225)us-gaap_ComprehensiveIncomeNetOfTax	$ 464us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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