CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 25,503	$ 81,378
Short-term investments	213,334	201,115
Accounts receivable	8,672	9,088
Prepaid expenses and other current assets	5,155	6,982
Total current assets	252,664	298,563
Property and equipment, net	20,382	21,586
Operating lease right-of-use assets	22,571	25,085
Intangible assets	1,320	1,320
Goodwill	4,228	4,228
Other long-term assets	1,087	1,055
Total assets	302,252	351,837
Current liabilities:
Accounts payable	2,542	2,228
Accrued expenses and other liabilities	23,715	26,068
Operating lease liabilities, current	5,906	5,866
Deferred revenue, current	44,810	19,723
Total current liabilities	76,973	53,885
Term debt	58,491	58,250
Operating lease liabilities, non-current	21,863	24,636
Deferred CIRM grant liability		3,992
Deferred revenue, noncurrent	18,787	21,333
Other long-term liabilities	2,478	2,146
Total liabilities	178,592	164,242
Commitments and Contingencies (Note 12)
Stockholders’ equity:
Common stock, $0.0001 par value: 250,000,000 shares authorized at September 30, 2023 and December 31, 2022; 95,573,526 and 85,964,161 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	10	9
Additional paid-in capital	692,792	658,596
Accumulated other comprehensive loss	(200)	(149)
Accumulated deficit	(568,942)	(470,861)
Total stockholders’ equity	123,660	187,595
Total liabilities and stockholders’ equity	$ 302,252	$ 351,837