Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Cash flows from operating activities:
Net loss			$ (21,546)	$ (9,057)
Adjustments to reconcile net loss to net cash used in operations:
Stock-based compensation expense			965	353
Capital contributions - in-kind services - related party				60
Change in fair value of derivative liabilities (including $1,165 and $311 for a related party)	$ 0	$ (311)	(1,229)	(311)
Change in fair value of tranche liability (including $331 and $0 for a related party)	0	0	(365)	0
Non-cash interest expense (including $1,384 and $577 for a related party)			1,443	577
Loss on extinguishment and on issuance of convertible promissory notes (including $169 and $2,134 for a related party)			186	2,134
Changes in assets and liabilities:
Prepaid expense and other current assets			(588)	(403)
Other non-current assets			(281)
Accounts payable			2,240	(1,832)
Accrued compensation			(1,073)	(221)
Accrued expenses and other current liabilities			268	208
Net cash used in operating activities			(19,980)	(8,492)
Cash flows from financing activities:
Proceeds from the issuance of redeemable convertible preferred stock, net of issuance costs				1,591
Proceeds from issuance of convertible promissory notes (including $3,402 and $9,993 from a related party), net of issuance costs			7,500	9,993
Cash acquired in connection with the Merger			102,113
Payment of deferred transaction costs and issuance costs			(2,346)	(22)
Net cash provided by financing activities			107,267	11,562
Net increase in cash and cash equivalents and restricted cash			87,287	3,070
Cash and cash equivalents and restricted cash, at beginning of the period			1,639	3,169
Cash and cash equivalents and restricted cash, at end of the period	88,926	6,239	88,926	6,239
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	88,426	6,239	88,426	6,239
Restricted cash	500		500
Total cash, cash equivalents and restricted cash, at end of the period	$ 88,926	$ 6,239	88,926	6,239
Supplemental disclosure of cash flow information:
Capital contributions - in-kind services - related party				60
Premium on issuance of convertible promissory notes (including $169 and $2,134 for a related party)			186	$ 2,134
Merger transaction costs recognized in additional paid-in capital			5,357
Recognition of AlloVir common stock outstanding at the closing of the Merger			104,990
Issuance of redeemable convertible preferred stock upon conversion of convertible promissory notes			3,695
Conversion of redeemable convertible preferred stock into common stock in connection with the Merger			49,694
Conversion of convertible promissory notes and accrued interest in connection with the Merger			$ 20,799