Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Cash flows from operating activities:
Net loss		$ (82,456)	$ (47,524)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation		4,777	4,405
Depreciation expense		320	193
Impairment of property and equipment	$ 1,900	1,883	1,592	$ 1,600
Write-off of deferred financing costs		140
Impairment of right-of-use assets		22,836
Net amortization of premium on short-term investments		(2,009)	(2,408)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets		(750)	565
Operating lease right-of-use assets		570	1,080
Other assets		1,111	(3,240)
Accounts payable		(774)	3,985
Accrued expenses and other current liabilities		(5,400)	(625)
Restructuring Liability		4,855
Operating lease liabilities		(2,437)	(857)
Deferred revenue		(1,325)	(1,412)
Net cash used in operating activities		(58,659)	(44,246)
Cash flows from investing activities:
Purchases of property and equipment		(2,396)	(260)
Purchases of short-term investments		(47,949)	(72,765)
Maturity of short-term investments		102,519	62,800
Net cash provided by (used in) investing activities		52,174	(10,225)
Cash flows from financing activities:
Proceeds from sale of common stock, purchase warrants and pre-funded warrants, net of issuance costs		8,819	50,000
Payment of deferred offering costs		(290)	(3,332)
Proceeds from exercise of stock options		3	103
Net cash provided by financing activities		8,532	46,771
Net increase (decrease) in cash, cash equivalents and restricted cash		2,047	(7,700)
Cash, cash equivalents and restricted cash, beginning of period		23,745	33,942	33,942
Cash, cash equivalents and restricted cash, end of period	$ 25,792	25,792	26,242	$ 23,745
Supplemental disclosure of non-cash financing and investing activities:
Property and equipment purchases included in accounts payable			8
Modification of lease agreement			4,931
Issuance Costs in accounts payable, accrued expenses, and other current liabilities			150
Other assets included in accounts payable and other current liabilities			2,740
Right of Use Asset in Exchange for Lease Liability		$ 13,667
Deferred offering costs included in accounts payable and accrued expenses			$ 161