Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 333,942	$ 375,723
Accounts receivable	56	68
Prepaid expenses and other current assets	7,125	2,584
Total current assets	341,123	378,375
Non-current assets:
Property and equipment, net	3,215	3,874
Operating lease right-of-use assets	20,570	23,274
Deferred tax assets	11,017	9,956
Restricted cash, non-current	2,704	2,704
Other non-current assets	304	1,085
Total non-current assets	37,810	40,893
Total assets	378,933	419,268
Current liabilities:
Accounts payable	2,124	1,242
Accrued research and development	6,152	5,826
Income taxes payable, current	221	5
Lease liability, current	5,304	5,101
Other current liabilities	4,743	5,540
Total current liabilities	18,544	17,714
Non-current liabilities:
Deferred revenue, non-current	110,242	110,242
Lease liability, non-current	15,150	17,838
Other liabilities	553	553
Total non-current liabilities	125,945	128,633
Total liabilities	144,489	146,347
Commitments and contingencies (Note 6)
Shareholders’ equity:
Euro deferred shares	0	0
Ordinary shares	399	399
Additional paid-in capital	955,781	944,407
Accumulated deficit	(721,736)	(671,885)
Total shareholders’ equity	234,444	272,921
Total liabilities and shareholders’ equity	$ 378,933	$ 419,268