Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities:
Net loss	$ (110,286)	$ (91,426)
Adjustments to reconcile net loss to net cash used in operating activities:
Loss on lease termination	59,085	0
Stock-based compensation expense	11,449	18,293
Depreciation and amortization expense	3,755	3,938
Amortization (accretion) of premium (discount) on marketable securities, net	(6,312)	(6,699)
Other	84	24
Changes in operating assets and liabilities:
Collaboration receivable	(2,212)	0
Tenant receivable	0	(265)
Prepaid expenses and other current assets	694	1,408
Operating lease right-of-use assets	2,799	4,794
Other noncurrent assets	(2,840)	931
Accounts payable	(79)	1,386
Accrued expenses and other current liabilities	(9,526)	(2,633)
Deferred revenue	(12,154)	44,474
Operating lease liability	(7,236)	(1,992)
Net cash used in operating activities	(72,779)	(27,767)
Cash flows from investing activities:
Purchases of property and equipment	(2,023)	(2,817)
Proceeds from sale of property and equipment	149	0
Purchases of marketable securities	(115,881)	(295,967)
Maturities of marketable securities	142,000	291,000
Net cash provided by (used in) investing activities	24,245	(7,784)
Cash flows from financing activities:
Payment of share issuance costs	0	(179)
Proceeds from exercise of stock options and ESPP, net	278	367
Tax withholding payments related to net share settlements of restricted stock units	(172)	(448)
Net cash provided by financing activities	106	35,740
Net (decrease) increase in cash, cash equivalents and restricted cash	(48,428)	189
Cash, cash equivalents and restricted cash at beginning of period	72,237	98,863
Cash, cash equivalents and restricted cash at end of period	23,809	99,052
Supplemental disclosure of noncash investing and financing information:
Purchases of property and equipment included in accounts payable and accrued expenses	47	1,330
Unrealized gains on marketable securities	45	79
ModernaTX, Inc
Cash flows from financing activities:
Proceeds from issuance/sale of common stock	$ 0	$ 36,000