Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash	$ 92,117	$ 63,380
Accounts receivable	201	5,021
Prepaid expenses and other current assets	4,884	2,076
Research and development incentives receivable	6,944	6,292
Total current assets	104,146	76,769
Property and equipment, net	2,292	1,818
Operating lease right‑of‑use assets	2,056
Other assets	1,700	3,039
Total assets	110,194	81,626
Current liabilities:
Accounts payable	1,949	1,887
Accrued expenses and other current liabilities	6,144	7,032
Deferred revenue, current portion	728	10
Total current liabilities	8,821	8,929
Warrant liability		4,804
Operating lease liabilities	1,251
Deferred revenue, net of current portion	4,929	14,625
Other long‑term liabilities	1,995	897
Total liabilities	16,996	29,255
Commitments and contingencies (Note 12)
Shareholders’ equity (deficit):
Ordinary shares, £0.01 nominal value; 31,995,653 and 15,452,420 shares authorized at December 31, 2019 and December 31, 2018, respectively; 17,993,701 shares issued and outstanding at December 31, 2019; 898,675 shares issued and 814,728 shares outstanding at December 31, 2018	227	10
Additional paid‑in capital	195,056	1,857
Accumulated other comprehensive loss	(1,535)	(1,751)
Accumulated deficit	(100,550)	(69,942)
Total shareholders’ equity (deficit)	93,198	(69,826)
Total liabilities, convertible preferred shares and shareholders’ equity (deficit)	$ 110,194	81,626
Series A Convertible Preferred Shares
Shareholders’ equity (deficit):
Convertible preferred shares		41,820
Series B1 Convertible Preferred Shares
Shareholders’ equity (deficit):
Convertible preferred shares		54,621
Series B2 Convertible Preferred Shares
Shareholders’ equity (deficit):
Convertible preferred shares		$ 25,756