CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities
Net loss	$ (25,946)	$ (79,679)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,141	1,539
Amortization and accretion income, net	2	11
Share-based compensation	14,545	15,832
Loss on disposal of property and equipment	(218)
Amortization of right-of-use assets	341	743
Undistributed earnings from TRC, LLC	(18,596)	4,751
Interest shortfall on 2035 notes, net	4,712
Other		46
Changes in operating assets and liabilities:
Receivables from collaborative and licensing arrangements	1,788	3,953
Prepaid clinical and development services	5,503	1,582
Other prepaid and current assets	2,436	322
Other assets	1	65
Accounts payable	(1,619)	(1,073)
Accrued personnel-related expenses, accrued clinical and development expenses, and other accrued liabilities	(10,344)	(17,299)
Accrued interest payable	1,901	1,830
Deferred revenue	(9)	(3,871)
Operating lease liabilities	(1,715)	1,159
Other long-term liabilities	8	224
Net cash used in operating activities	(26,069)	(69,865)
Investing activities
Purchases of property and equipment	(250)	(1,767)
Purchases of marketable securities	(18,174)	(36)
Maturities of marketable securities	48,499	115,500
Proceeds from the sale of property and equipment	1,849
Net cash provided by (used in) investing activities	31,924	113,697
Financing activities
Principal payment on 2035 notes		(5,698)
Principal payment on 2033 notes		(5,698)
Proceeds from option exercises		3
Repurchase of shares to satisfy tax withholding	(1,448)	(5,593)
Net cash provided by financing activities	(1,448)	(11,288)
Net increase (decrease) in cash, cash equivalents, and restricted cash	4,407	32,544
Cash, cash equivalents, and restricted cash at beginning of period	90,796	82,300
Cash, cash equivalents, and restricted cash at end of period	95,203	114,844
Supplemental disclosure of cash flow information
Cash paid for interest	$ 4,613	$ 14,385