Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 111,510	$ 148,380
Prepaid expenses	4,731	4,037
Tax and tax incentive receivable	20,185	15,583
Other current assets	2,206	2,063
Total current assets	138,632	170,063
Non-current assets:
Furniture and equipment, net	91	80
Goodwill	545	545
Equity interest	15,000	15,000
Right-of-use assets	588	899
Total non-current assets	16,224	16,524
Total assets	154,856	186,587
Current liabilities:
Accounts payable	9,364	10,044
Accrued expenses	28,603	22,256
Operating lease liability	464	648
Taxes payable	311	147
Other current liabilities	121	327
Total current liabilities	38,863	33,422
Non-current liabilities:
Term loan	4,981	4,874
Operating lease liability	132	286
Total non-current liabilities	5,113	5,160
Total liabilities	43,976	38,582
Commitments and contingencies
Shareholders' equity:
Ordinary £0.05 par value shares; 494,058,246 and 489,177,550 issued, and 485,298,326 and 480,082,966 outstanding, at June 30, 2022 and December 31, 2021, respectively	32,182	31,855
Additional paid-in capital	390,543	385,070
Ordinary shares held in treasury	(591)	(603)
Accumulated other comprehensive loss	(4,601)	(4,601)
Accumulated deficit	(306,653)	(263,716)
Total shareholders' equity	110,880	148,005
Total liabilities and shareholders' equity	$ 154,856	$ 186,587