CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
ASSETS
Cash and cash equivalents	$ 478,750	$ 293,856
Accounts receivable	4,467	35
Unbilled receivable	2,345	11
Contract assets	3,000
Non-cash royalty receivable	4,115	22,451
Prepaid and other current assets	7,322	7,901
Total current assets	499,999	324,254
Property and equipment, net of accumulated depreciation	4,663	5,760
Operating lease right-of-use assets	12,392	14,072
Other assets	8,711	10,986
Total assets	525,765	355,072
LIABILITIES AND SHAREHOLDERS' EQUITY
Accounts payable	18,434	9,538
Accrued compensation	5,469	4,620
Other accrued liabilities	23,077	29,320
Convertible 4.5% senior notes, net of deferred financing costs of $0 and $7, respectively		2,093
Current portion of liability related to the sale of future royalties, net of deferred financing costs of $198 and $319, respectively	6,077	44,357
Current portion of operating lease liability	3,537	3,146
Current portion of deferred revenue	44,351	29,249
Total current liabilities	100,945	122,323
Deferred revenue, net of current portion	47,717	80,860
Operating lease liability, net of current portion	15,244	18,651
Liability related to the sale of future royalties, net of current portion and deferred financing costs of $381 and $584, respectively	34,967	41,082
Other long-term liabilities	1,306	2,586
Total liabilities	200,179	265,502
Commitments and contingencies (Note I)
Shareholders' deficit:
Preferred stock, $.01 par value; authorized 5,000 shares; no shares issued and outstanding as of each of December 31, 2021 and December 31, 2020
Common stock, $.01 par value; authorized 300,000 shares; 220,361 and 194,998 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively	2,204	1,950
Additional paid-in capital	1,794,525	1,419,460
Accumulated deficit	(1,471,143)	(1,331,840)
Total shareholders' equity	325,586	89,570
Total liabilities and shareholders' equity	$ 525,765	$ 355,072