CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue
Total revenue	$ 5,362	$ 0	$ 6,071	$ 0
Expenses
Research and development	128,339	134,575	259,315	238,646
General and administrative	54,228	29,611	108,179	57,961
Total operating expenses	182,567	164,186	367,494	296,607
Loss from operations	(177,205)	(164,186)	(361,423)	(296,607)
Other income (expense), net	760	(2,244)	(3,408)	(5,503)
Net loss	(176,445)	(166,430)	(364,831)	(302,110)
Unrealized (loss) gain on available-for-sale investments	(909)	145	(5,711)	(158)
Comprehensive loss	$ (177,354)	$ (166,285)	$ (370,542)	$ (302,268)
Basic net loss per share (USD per share)	$ (3.18)	$ (3.23)	$ (6.57)	$ (5.91)
Diluted net loss per share (USD per share)	$ (3.18)	$ (3.23)	$ (6.57)	$ (5.91)
Weighted average common shares outstanding, basic (shares)	55,552,438	51,472,901	55,510,649	51,128,048
Weighted average common shares outstanding, diluted (shares)	55,552,438	51,472,901	55,510,649	51,128,048