Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Cash flows from operating activities:
Net loss			$ (70,583)	$ (31,873)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation			3,286	2,964
Depreciation expense			281	261
Impairment of property and equipment	$ 1,883	$ 1,592	1,883	1,592	$ 1,600
Write-off of deferred financing costs			140
Impairment of right-of-use assets	22,836		22,836
Net amortization of premium on short-term investments			(1,608)	(1,352)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets			131	1,135
Operating lease right-of-use assets			227	803
Other assets			1,111	(2,527)
Accounts payable			1,818	3,189
Accrued expenses and other current liabilities			(2,502)	(2,928)
Restructuring Liability			3,127
Operating lease liabilities			(1,453)	(528)
Deferred revenue			(1,130)	(868)
Net cash used in operating activities			(42,436)	(30,132)
Cash flows from investing activities:
Purchases of property and equipment			(2,345)	(116)
Purchases of short-term investments			(35,141)	(29,930)
Maturity of short-term investments			81,519	34,800
Net cash provided by investing activities			44,033	4,754
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			(267)	(2,912)
Proceeds from exercise of stock options			3	101
Net cash provided by financing activities			8,555	47,189
Net increase in cash, cash equivalents and restricted cash			10,152	21,811
Cash, cash equivalents and restricted cash, beginning of period			23,745	33,942	33,942
Cash, cash equivalents and restricted cash, end of period	$ 33,897	$ 55,753	33,897	55,753	$ 23,745
Supplemental disclosure of non-cash financing and investing activities:
Property and equipment purchases included in accounts payable			64	54
Other assets included in accounts payable and other current liabilities				505
Right of Use Asset in Exchange for Lease Liability			13,667
Prepaid expenses for right-of-use asset included in operating lease liabilities			440
Deferred offering costs included in accounts payable and accrued expenses			$ 23	$ 420