Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 147,914	$ 173,415
Short-term investments	351,394	555,231
Receivable from collaboration partners ($744,535 and $943 from a related party)	744,595	1,049
Accrued interest receivable	2,227	649
Prepaid expenses and other current assets	15,620	5,471
Total current assets	1,261,750	735,815
Long-term investments	181,990	6,440
Property and equipment, net	32,455	10,807
Right-of-use assets	104,968	12,781
Restricted cash	3,005	203
Other long-term assets	7,730	6,246
Total assets	1,591,898	772,292
Current liabilities:
Accounts payable	10,261	15,682
Accrued research and development	29,587	18,307
Other accrued liabilities	24,181	9,543
Deferred revenue, current ($96,981 and $67,571 to a related party)	102,003	74,571
Other current liabilities	52	3,566
Total current liabilities	166,084	121,669
Deferred revenue, noncurrent ($462,217 and $127,511 to a related party)	462,217	132,533
Operating lease liabilities, noncurrent	116,887	15,243
Other long-term liabilities	5,260	543
Total liabilities	750,448	269,988
Commitments (Note 12)
Stockholders’ equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of December 31, 2021 and 2020; no shares issued and outstanding as of December 31, 2021 and 2020	0	0
Common stock, $0.0001 par value, 400,000,000 shares authorized as of December 31, 2021 and 2020; 70,781,736 and 65,114,685 shares issued and outstanding as of December 31, 2021 and 2020, respectively.Shares outstanding incudes 9,946 and 2020, respectively. Shares outstanding incudes 9,946 and 1,422,784 shares issued but subject to vesting as of December 31, 2021and 2020, respectively.	7	6
Additional paid-in capital	1,118,058	830,438
Accumulated deficit	(275,354)	(328,184)
Accumulated other comprehensive income (loss)	(1,261)	44
Total stockholders’ equity	841,450	502,304
Total liabilities and stockholders’ equity	$ 1,591,898	$ 772,292