Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Cash flows from operating activities:
Net loss	$ (10,196)	$ (3,407)
Adjustments to reconcile net loss to net cash used in operations:
Stock-based compensation expense	374	31
Capital contributions - in-kind services - related party		60
Change in fair value of derivative liabilities (including $1,165 and $0 for a related party)	(1,229)	0
Change in fair value of tranche liability (including $331 and $0 for a related party)	(365)	0
Non-cash interest expense (including $1,384 and $71 for a related party)	1,443	78
Loss on issuance of convertible promissory notes (including $169 and $793 for a related party)	186	793
Changes in assets and liabilities:
Prepaid expense and other current assets	1,420	(395)
Accounts payable	934	(1,235)
Accrued compensation	(1,387)	(278)
Accrued research and development expenses	1,227	(242)
Accrued expenses and other current liabilities	152	74
Net cash used in operating activities	(7,441)	(4,521)
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 $4,993 from a related party), net of issuance costs	7,500	4,993
Cash acquired in connection with the Merger	102,113
Payment of deferred transaction costs and issuance costs	(2,346)	(5)
Net cash provided by financing activities	107,267	6,579
Net increase in cash and cash equivalents and restricted cash	99,826	2,058
Cash and cash equivalents, at beginning of the period	1,639	3,169
Cash and cash equivalents and restricted cash, at end of the period	101,465	5,227
Reconciliation of cash, cash equivalents and restricted cash to statement of financial position
Cash and cash equivalents	100,965	5,227
Restricted cash	500
Cash and cash equivalents and restricted cash, at end of the period	101,465	5,227
Supplemental disclosure of cash flow information:
Capital contributions - in-kind services - related party		60
Premium on issuance of convertible promissory notes (including $169 and $793 for a related party)	186	$ 793
Merger transaction costs recognized in additional paid-in capital	5,357
Unpaid deferred transaction costs included in accounts payable and other accrued expenses and current liabilities	629
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