Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash	$ 195,901	$ 135,990
Accounts receivable	2,000	5,456
Prepaid expenses and other current assets	5,962	5,100
Research and development incentives receivable	11,530	9,177
Total current assets	215,393	155,723
Property and equipment, net	2,550	2,317
Operating lease right-of-use assets	3,721	1,290
Other assets	2,178	1,822
Total assets	223,842	161,152
Current liabilities:
Accounts payable	996	1,365
Accrued expenses and other current liabilities	9,716	11,629
Deferred revenue, current portion	10,094	10,135
Total current liabilities	20,806	23,129
Long-term debt, net of discount	29,498	14,505
Operating lease liabilities, net of current portion	3,025	426
Deferred revenue, net of current portion	25,616	25,021
Other long-term liabilities	2,806	2,611
Total liabilities	81,751	65,692
Commitments and contingencies (Note 11)
Shareholders’ equity:
Ordinary shares, £0.01 nominal value; 31,995,653 shares authorized at March 31, 2021 and December 31, 2020; 23,516,587 and 21,094,557 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	300	266
Additional paid-in capital	312,793	249,947
Accumulated other comprehensive loss	(3,251)	(3,193)
Accumulated deficit	(167,751)	(151,560)
Total shareholders’ equity	142,091	95,460
Total liabilities and shareholders’ equity	$ 223,842	$ 161,152