Commitments and Contingencies	12 Months Ended
Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	13. Commitments and Contingencies Leases The Company entered into a lease agreement and a sublease agreement for the lease of property in Waltham, Massachusetts (see Note 5 and Note 16). Legal Proceedings From time to time, in the ordinary course of business, the Company is subject to litigation and regulatory examinations as well as information gathering requests, inquiries and investigations. On January 19, 2024, a purported stockholder of the Company filed a lawsuit, captioned Zerbato v. AlloVir, Inc. et al., No. 1:24-cv-10152 (D. Mass.), in Massachusetts federal court against the Company and two of its officers purportedly on behalf of a putative class of stockholders consisting of persons who purchased or otherwise acquired Company securities between March 22, 2022 and December 21, 2023, inclusive. The complaint purports to assert claims under Section 10(b) and 20(a) of the Securities Act of 1934, as amended, and the related regulations, alleging that the defendants made false and misleading statements and omissions to investors relating to the Company’s three Phase 3 studies of posoleucel. The complaint seeks, among other things, damages, prejudgment and post-judgment interest, and attorneys’ fees, expert fees and other costs. The Company intends to vigorously defend against the lawsuit. As the outcome is not presently determinable, any loss is neither probable nor reasonably estimable. Purchase and Other Obligations We enter into contracts in the normal course of business with CROs and other third-party vendors for clinical trials and testing and manufacturing services, which can contain purchase commitments or other noncancelable obligations. Most contracts do not contain minimum purchase commitments and are cancellable by us upon written notice. Payments due upon cancellation consist of payments for services provided or expenses incurred, including non-cancelable obligations of services provided up to one year after the date of cancellation. The amount and timing of such payments are not known. We may incur potential contingent payments upon our achievement of clinical, regulatory and commercial milestones, as applicable, or we may be required to make royalty payments under license and grant agreements we have entered into with various entities pursuant to which we have in-licensed certain intellectual property. Due to the uncertainty of the achievement and timing of the events requiring payment under these agreements, the amounts to be paid by us are not fixed or determinable at this time (see Note 8).

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

13. Commitments and Contingencies

Leases

The Company entered into a lease agreement and a sublease agreement for the lease of property in Waltham, Massachusetts (see Note 5 and Note 16).

Legal Proceedings

From time to time, in the ordinary course of business, the Company is subject to litigation and regulatory examinations as well as information gathering requests, inquiries and investigations. On January 19, 2024, a purported stockholder of the Company filed a lawsuit, captioned Zerbato v. AlloVir, Inc. et al., No. 1:24-cv-10152 (D. Mass.), in Massachusetts federal court against the Company and two of its officers purportedly on behalf of a putative class of stockholders consisting of persons who purchased or otherwise acquired Company securities between March 22, 2022 and December 21, 2023, inclusive. The complaint purports to assert claims under Section 10(b) and 20(a) of the Securities Act of 1934, as amended, and the related regulations, alleging that the defendants made false and misleading statements and omissions to investors relating to the Company’s three Phase 3 studies of posoleucel. The complaint seeks, among other things, damages, prejudgment and post-judgment interest, and attorneys’ fees, expert fees and other costs. The Company intends to vigorously defend against the lawsuit. As the outcome is not presently determinable, any loss is neither probable nor reasonably estimable.

Purchase and Other Obligations

We enter into contracts in the normal course of business with CROs and other third-party vendors for clinical trials and testing and manufacturing services, which can contain purchase commitments or other noncancelable obligations. Most contracts do not contain minimum purchase commitments and are cancellable by us upon written notice. Payments due upon cancellation consist of payments for services provided or expenses incurred, including non-cancelable obligations of services provided up to one year after the date of cancellation. The amount and timing of such payments are not known.

We may incur potential contingent payments upon our achievement of clinical, regulatory and commercial milestones, as applicable, or we may be required to make royalty payments under license and grant agreements we have entered into with various entities pursuant to which we have in-licensed certain intellectual property. Due to the uncertainty of the achievement and timing of the events requiring payment under these agreements, the amounts to be paid by us are not fixed or determinable at this time (see Note 8).