Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flow from operating activities
Net loss	$ (22,782)	$ (76,906)
Adjustments to reconcile net loss (income) to net cash used in operating activities:
Stock-based compensation expense	6,998	9,670
Depreciation	5,357	3,683
Amortization of premiums and discounts on marketable securities	(23)	324
Other non-cash items	(2,468)	(2,460)
Changes in operating assets and liabilities:
Accounts receivable	(10,000)
Related party collaboration receivable	507	6,847
Prepaid expenses and other current assets	(1,652)	1,731
Operating lease, right-of-use asset	3,005	2,265
Other non-current assets		69
Accounts payable	763	(42)
Accrued expenses	1,536	(2,912)
Operating lease liabilities	(3,280)	(2,348)
Other non-current liabilities	(151)
Deferred revenue	21,925	(4,641)
Net cash used in operating activities	(265)	(64,720)
Cash flow from investing activities
Purchases of property and equipment	(1,558)	(1,262)
Purchases of marketable securities	(54,848)
Proceeds from sales and maturities of marketable securities	35,000	72,632
Net cash (used in) provided by investing activities	(21,406)	71,370
Cash flow from financing activities
Proceeds from the exercise of stock options	602	28
Proceeds from the purchase of common stock under ESPP	232	357
Net cash provided by financing activities	834	385
Net (decrease) increase in cash, cash equivalents, and restricted cash	(20,837)	7,035
Cash, cash equivalents, and restricted cash beginning of period	119,212	106,219
Cash, cash equivalents, and restricted cash end of period	98,375	113,254
Supplemental disclosure of cash and non-cash activities
Capital expenditures incurred but not yet paid	$ 40	$ 22