Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating activities
Net loss	$ (70,259)	$ (68,920)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	17,561	15,783
Depreciation of property and equipment	2,041	1,120
Non-cash lease expense	448	1,165
Non-cash interest expense, net	1,698	1,771
Changes in assets and liabilities:
Accounts receivable, net	(4,348)	19
Accounts receivable from related party	(144)	(21)
Inventory	(4,623)	0
Prepaids and other current assets	(2,891)	994
Other assets	92	19
Accounts payable	846	2,636
Operating lease liabilities	(1,363)	8,094
Other liabilities	1,091	(214)
Deferred revenue from related party	42,556	(1,864)
Net cash used in operating activities	(17,295)	(39,418)
Investing activities
Purchases of property and equipment, net	(628)	(14,177)
Purchases of investments	(126,757)	(198,944)
Maturities of investments	134,128	299,555
Net cash provided by investing activities	6,743	86,434
Financing activities
Proceeds from exercise of stock options and employee stock purchase plan	8,096	3,165
Employees' tax withheld and paid for with restricted stock units	(3,126)	(5,273)
Net cash provided by (used in) financing activities	4,970	(2,108)
Net (decrease) increase in cash, cash equivalents and restricted cash	(5,582)	44,908
Cash, cash equivalents and restricted cash at beginning of period	51,058	33,377
Cash, cash equivalents and restricted cash at end of period	45,476	78,285
Supplemental disclosures of cash flow information
Cash paid for interest	986	1,029
Right-of-use assets obtained in exchange for lease obligations	1	455
Purchases of property and equipment, net recorded in accounts payable and accrued liabilities	$ 0	$ 4,436