Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues:
Total revenues	$ 9,461	$ 64,530	$ 28,383	$ 68,030
Operating expenses:
Research and development (($756), ($2,971), ($6,856) and ($2,971) from a related party)	71,254	51,801	206,412	110,636
General and administrative	16,343	11,177	48,990	29,617
Total operating expenses	87,597	62,978	255,402	140,253
Income (loss) from operations	(78,136)	1,552	(227,019)	(72,223)
Non-operating income (expense):
Interest and other income, net	161	270	481	1,218
Gain on deemed sale from equity method investee				613
Share of loss from equity method investee				(613)
Total non-operating income, net	161	270	481	1,218
Net income (loss)	(77,975)	1,822	(226,538)	(71,005)
Other comprehensive income (loss)	(46)	(63)	(136)	17
Comprehensive income (loss)	$ (78,021)	$ 1,759	$ (226,674)	$ (70,988)
Net income (loss) per share, basic	$ (1.11)	$ 0.03	$ (3.28)	$ (1.37)
Weighted-average number of shares used to compute basic net income (loss) per share	70,110,138	62,599,193	68,990,290	51,852,247
Net income (loss) per share, diluted	$ (1.11)	$ 0.03	$ (3.28)	$ (1.37)
Weighted-average number of shares used to compute diluted net income (loss) per share	70,110,138	65,145,707	68,990,290	51,852,247
License Revenue
Revenues:
Total revenues		$ 55,096		$ 55,096
Collaboration Revenue
Revenues:
Total revenues	$ 9,461	$ 9,434	$ 28,383	$ 12,934