Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 303,851	$ 176,677
Receivable from Roche	1,491	0
Receivable from related party	46	58
Deferred tax assets	82	81
Prepaid expenses and other current assets	1,549	1,406
Total current assets	307,019	178,222
Non-current assets:
Property and equipment, net	3,340	3,372
Deferred tax assets, non-current	1,298	816
Other non-current assets	28	0
Total non-current assets	4,666	4,188
Total assets	311,685	182,410
Current liabilities:
Accounts payable	1,483	1,790
Accrued research and development	5,730	1,542
Income taxes payable	406	184
Other current liabilities	3,692	3,890
Total current liabilities	11,311	7,406
Non-current liabilities:
Income taxes payable, non-current	19	0
Deferred rent	1,936	1,734
Total non-current liabilities	1,955	1,734
Total liabilities	13,266	9,140
Commitments and contingencies (Note 6)
Shareholders’ equity:
Euro deferred shares, €22 nominal value: Authorized shares - 10,000 at June 30, 2014 and December 31, 2013 Issued and outstanding shares - none at June 30, 2014 and December 31, 2013	0	0
Ordinary shares, $0.01 par value: Authorized shares - 100,000,000 at June 30, 2014 and December 31, 2013 Issued and outstanding shares - 26,663,437 and 21,856,261 at June 30, 2014 and December 31, 2013	267	219
Additional paid-in capital	320,351	214,392
Accumulated deficit	(22,199)	(41,341)
Total shareholders’ equity	298,419	173,270
Total liabilities and shareholders’ equity	$ 311,685	$ 182,410