Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating activities
Net loss	$ (141,795)	$ (100,222)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,723	2,125
Stock-based compensation	39,873	26,230
Accretion and amortization of premiums and discounts on investments, net	1,398	2,629
Amortization of collaboration contract assets	763	1,602
Deferred revenue	2,793	(5,208)
Change in fair value of stock price appreciation milestones	(14,240)	7,956
Changes in operating assets and liabilities:
Accounts receivable	(4,450)	(4,788)
Prepaid expenses and other assets	(8,136)	(1,669)
Accounts payable and accrued expenses	586	9,550
Right-of-use assets and lease liabilities, net	(287)	2,593
Net cash used in operating activities	(117,772)	(59,202)
Investing activities
Purchases of property and equipment	(20,213)	(17,600)
Purchases of investments	(196,115)	(629,244)
Maturities of investments	249,589	173,584
Net cash provided by (used in) investing activities	33,261	(473,260)
Financing activities
Issuance of common stock from equity incentive plans, net of issuance costs	6,203	9,323
Proceeds from public offering of common stock and issuance of pre-funded warrants, net of issuance costs	0	432,446
Net cash provided by financing activities	6,203	441,769
Net change in cash, cash equivalents and restricted cash	(78,308)	(90,693)
Cash, cash equivalents and restricted cash at beginning of the period	148,810	182,574
Cash, cash equivalents and restricted cash at end of the period	70,502	91,881
Supplemental schedule of noncash investing and financing activities
Purchases of property and equipment in accounts payable	1,469	1,435
Right-of use assets obtained in exchange for lease obligations	$ 518	$ 1,546