CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 81,467	$ 58,064
Short-term marketable securities	211,474	222,767
Receivables from collaborative arrangements	15,868	11,996
Receivables from licensing arrangements		10,000
Amounts due from TRC, LLC	53,799	28,574
Prepaid clinical and development services	20,374	2,736
Other prepaid and current assets	10,359	4,351
Total current assets	393,341	338,488
Property and equipment, net	16,422	12,644
Long-term marketable securities		4,985
Operating lease assets	43,260	46,604
Equity in net assets of TRC, LLC	12,750
Tax receivable		3,682
Restricted cash	833	833
Other assets	2,451	1,590
Total assets	469,057	408,826
Current liabilities:
Accounts payable	6,775	4,758
Accrued personnel-related expenses	35,238	28,180
Accrued clinical and development expenses	28,799	17,587
Accrued general and administrative expenses	6,048	4,394
Accrued interest payable	3,974	5,659
Current portion of non-recourse notes due 2035, net	19,334
Current portion of non-recourse notes due 2033, net		9,851
Operating lease liabilities	9,867	7,762
Deferred revenue	11,523	31,575
Other accrued liabilities	2,013	1,937
Total current liabilities	123,571	111,703
Convertible senior notes due 2023, net	226,963	225,890
Non-recourse notes due 2035, net	372,873
Non-recourse notes due 2033, net		219,300
Long-term operating lease liabilities	47,220	47,725
Long-term deferred revenue	348	6,761
Other long-term liabilities	1,833	21,287
Commitments and contingencies
Shareholders' Deficit
Preferred shares, $0.00001 par value: 230 shares authorized, no shares issued or outstanding
Ordinary shares, $0.00001 par value: 200,000 shares authorized; 64,328 and 57,015 shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively	1	1
Additional paid-in capital	1,222,818	1,024,614
Accumulated other comprehensive income	47	145
Accumulated deficit	(1,526,617)	(1,248,600)
Total shareholders' deficit	(303,751)	(223,840)
Total liabilities and shareholders' deficit	$ 469,057	$ 408,826