CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues:
Total revenues	$ 268	$ 163	$ 1,234	$ 337
Operating expenses:
Research and development	26,252	20,731	53,049	37,786
General and administrative	7,221	7,154	13,861	14,066
Gain on fair value remeasurement of contingent consideration	0	(6,326)	0	(6,862)
Litigation settlement related loss		15,000	0	15,000
Total operating expenses	33,473	36,559	66,910	59,990
Operating loss	(33,205)	(36,396)	(65,676)	(59,653)
Investment and other income, net	2,703	392	5,813	599
Net loss	$ (30,502)	$ (36,004)	$ (59,863)	$ (59,054)
Basic and diluted net loss per common share	$ (0.65)	$ (0.77)	$ (1.27)	$ (1.26)
Basic and diluted net loss per common share	$ (0.65)	$ (0.77)	$ (1.27)	$ (1.26)
Shares used in calculating basic and diluted net loss per share	47,253	46,759	47,233	46,749
Shares used in calculating basic and diluted net loss per share	47,253	46,759	47,233	46,749
Comprehensive loss:
Net loss	$ (30,502)	$ (36,004)	$ (59,863)	$ (59,054)
Other comprehensive income (loss):
Unrealized (loss) gain on marketable securities	(51)	(529)	812	(2,311)
Comprehensive loss	(30,553)	(36,533)	(59,051)	(61,365)
Product development and licensing agreements
Revenues:
Total revenues	16		16	30
Contracts and grants
Revenues:
Total revenues	$ 252	$ 163	$ 1,218	$ 307