Commitments and Contingencies	12 Months Ended
Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies 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. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. Legal fees and other costs associated with such proceedings are expensed as incurred. We do not have any legal proceedings that, based on our estimates, are expected to have a material effect on our consolidated financial statements. 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.) (the “Securities Class Action”), in the U.S. District Court for the District of Massachusetts against the Company and two of its officers purportedly on behalf of a putative class of stockholders. On April 16, 2024, the Court appointed stockholders Harry Levin and Julio Maurice Bueno as lead plaintiffs and their counsel as lead counsel in the action. On June 17, 2024, lead plaintiffs filed their amended complaint. In the amended complaint, lead plaintiffs assert claims purportedly on behalf of a putative class of stockholders consisting of persons who purchased or otherwise acquired Company securities between January 11, 2023 and December 21, 2023, inclusive. The amended complaint asserts claims under Sections 10(b) and 20(a) of the Securities Exchange 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. Defendants filed their motion to dismiss the amended complaint on August 16, 2024, which was fully briefed as of December 12, 2024. Oral argument on the motion to dismiss was held on February 19, 2025. On March 3, 2025, the parties jointly informed the Court that they had reached a settlement in principle, subject to the execution of a definitive settlement agreement and Court approval. On March 4, 2025, the Court denied Defendants’ motion to dismiss as moot in light of the settlement in principle. On July 3, 2024, a purported stockholder of the Company filed a derivative lawsuit, captioned Steffens v. Brainard et al., No. 1:24-cv-11721 (D. Mass.), in the U.S. District Court for the District of Massachusetts against certain of the Company’s officers and directors and naming the Company as a nominal defendant. The derivative complaint alleged, purportedly on behalf of the Company, violations of Section 10(b) of the Securities Exchange Act of 1934 and Rule 10b-5 thereunder, breach of fiduciary duty, aiding and abetting breach of fiduciary duty, unjust enrichment, and waste of corporate assets against the individual defendants. These claims were based on substantially identical allegations as the complaint in the above-listed Securities Class Action. The lawsuit sought, among other things, an award of damages and restitution in favor of the Company, certain changes to the Company’s corporate governance, punitive damages, and attorneys’ fees and costs. On October 21, 2024, the court ordered plaintiff to file timely proof of service or show cause why the case should not be dismissed for failure to effect timely service by November 4, 2024. On November 4, 2024, plaintiff voluntarily dismissed the derivative lawsuit. On October 21, 2024, a purported stockholder of the Company filed a derivative lawsuit, captioned Lister v. Brainard et al., No. 1:24-cv-12658 (D. Mass.), in the U.S. District Court for the District of Massachusetts against certain of the Company’s officers and directors and naming the Company as a nominal defendant. The derivative complaint alleges, purportedly on behalf of the Company, violations of Section 14(a) of the Securities Exchange Act of 1934, breach of fiduciary duties, unjust enrichment, waste of corporate assets, gross mismanagement, and abuse of control against the individual defendants and contribution under Sections 10(b) and 21D of the Securities Exchange Act of 1934 against Ms. Brainard and Mr. Sinha. These claims are based on substantially identical allegations as the complaint in the above-listed Securities Class Action. The lawsuit seeks, among other things, an award of damages and restitution in favor of the Company, certain changes to the Company’s corporate governance, and attorneys’ fees and costs. On February 24, 2025, the Company filed an unopposed motion to stay the case pending a ruling on the motion to dismiss in the Securities Class Action. Merger Agreement On November 7, 2024, the Company entered into the Merger Agreement pursuant to which, subject to the satisfaction or waiver of various conditions therein, Merger Sub will merge with and into Kalaris, with Kalaris surviving as the wholly-owned subsidiary. The Merger was unanimously approved by The Company's Board. The closing of the Merger is subject to the satisfaction or waiver of various conditions, by each of the parties, at or prior to the closing of the Merger, including, among other things, (i) the approval by AlloVir stockholders of (a) the issuance of shares of AlloVir common stock, which represent more than 20% of the shares of AlloVir common stock outstanding immediately prior to the Merger, to Kalaris stockholders pursuant to the terms of the Merger Agreement and pursuant to Nasdaq Listing Rule 5635(a) and (b) the change of control of AlloVir resulting from the Merger, and (ii) the adoption of the Merger Agreement by the requisite Kalaris stockholders. If the Company is unable to satisfy certain closing conditions to the Merger Agreement or if other mutual closing conditions to the Merger Agreement are not satisfied, Kalaris will not be obligated to complete the Merger. The Merger Agreement contains certain termination rights of each of AlloVir and Kalaris. Under certain circumstances detailed in the Merger Agreement, the Company could be required to pay Kalaris a termination fee of $3.48 million or Kalaris could be required to pay AlloVir a termination fee of $10.41 million. In addition, in certain circumstances upon the termination of the Merger Agreement, the Company could be required to pay the reasonable costs and expenses of Kalaris in an amount not to exceed $580,000, or Kalaris could be required to pay AlloVir's reasonable costs and expenses in an amount not to exceed $580,000. Additional Permitted Bridge Financing Pursuant to the Merger Agreement, Kalaris is permitted to enter into the Additional Permitted Bridge Financing. On January 10, 2025, as a part of the first tranche of the Additional Permitted Bridge Financing, Kalaris issued the AlloVir Note under which the Company funded a principal amount of $3.75 million, and Kalaris issued convertible promissory notes in an aggregate principal amount of $3.75 million to existing Kalaris stockholders (see Note 16). Prior to the closing of the merger, Kalaris has the opportunity to receive an additional $7.5 million in the second tranche of the Additional Permitted Financing of which $3.75 million would be provided by existing Kalaris stockholders and the remaining $3.75 million would be provided by AlloVir. However, Kalaris no longer expects the second tranche of the Additional Permitted Financing to be funded. Upon the closing of the Merger, the AlloVir Note will be cancelled and the aggregate amount outstanding under the AlloVir Note will be added to the Company's net cash. Other Obligations The Company may incur potential contingent payments upon the Company's achievement of clinical, regulatory and commercial milestones, as applicable, or the Company may be required to make royalty payments under license and grant agreements the Company has entered into with various entities pursuant to which the Company has 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 7).

Commitments and Contingencies

12 Months Ended

Dec. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

12. Commitments and Contingencies

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. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. Legal fees and other costs associated with such proceedings are expensed as incurred. We do not have any legal proceedings that, based on our estimates, are expected to have a material effect on our consolidated financial statements.

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.) (the “Securities Class Action”), in the U.S. District Court for the District of Massachusetts against the Company and two of its officers purportedly on behalf of a putative class of stockholders. On April 16, 2024, the Court appointed stockholders Harry Levin and Julio Maurice Bueno as lead plaintiffs and their counsel as lead counsel in the action. On June 17, 2024, lead plaintiffs filed their amended complaint. In the amended complaint, lead plaintiffs assert claims purportedly on behalf of a putative class of

stockholders consisting of persons who purchased or otherwise acquired Company securities between January 11, 2023 and December 21, 2023, inclusive. The amended complaint asserts claims under Sections 10(b) and 20(a) of the Securities Exchange 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. Defendants filed their motion to dismiss the amended complaint on August 16, 2024, which was fully briefed as of December 12, 2024. Oral argument on the motion to dismiss was held on February 19, 2025. On March 3, 2025, the parties jointly informed the Court that they had reached a settlement in principle, subject to the execution of a definitive settlement agreement and Court approval. On March 4, 2025, the Court denied Defendants’ motion to dismiss as moot in light of the settlement in principle.

On July 3, 2024, a purported stockholder of the Company filed a derivative lawsuit, captioned Steffens v. Brainard et al., No. 1:24-cv-11721 (D. Mass.), in the U.S. District Court for the District of Massachusetts against certain of the Company’s officers and directors and naming the Company as a nominal defendant. The derivative complaint alleged, purportedly on behalf of the Company, violations of Section 10(b) of the Securities Exchange Act of 1934 and Rule 10b-5 thereunder, breach of fiduciary duty, aiding and abetting breach of fiduciary duty, unjust enrichment, and waste of corporate assets against the individual defendants. These claims were based on substantially identical allegations as the complaint in the above-listed Securities Class Action. The lawsuit sought, among other things, an award of damages and restitution in favor of the Company, certain changes to the Company’s corporate governance, punitive damages, and attorneys’ fees and costs. On October 21, 2024, the court ordered plaintiff to file timely proof of service or show cause why the case should not be dismissed for failure to effect timely service by November 4, 2024. On November 4, 2024, plaintiff voluntarily dismissed the derivative lawsuit.

On October 21, 2024, a purported stockholder of the Company filed a derivative lawsuit, captioned Lister v. Brainard et al., No. 1:24-cv-12658 (D. Mass.), in the U.S. District Court for the District of Massachusetts against certain of the Company’s officers and directors and naming the Company as a nominal defendant. The derivative complaint alleges, purportedly on behalf of the Company, violations of Section 14(a) of the Securities Exchange Act of 1934, breach of fiduciary duties, unjust enrichment, waste of corporate assets, gross mismanagement, and abuse of control against the individual defendants and contribution under Sections 10(b) and 21D of the Securities Exchange Act of 1934 against Ms. Brainard and Mr. Sinha. These claims are based on substantially identical allegations as the complaint in the above-listed Securities Class Action. The lawsuit seeks, among other things, an award of damages and restitution in favor of the Company, certain changes to the Company’s corporate governance, and attorneys’ fees and costs. On February 24, 2025, the Company filed an unopposed motion to stay the case pending a ruling on the motion to dismiss in the Securities Class Action.

Merger Agreement

On November 7, 2024, the Company entered into the Merger Agreement pursuant to which, subject to the satisfaction or waiver of various conditions therein, Merger Sub will merge with and into Kalaris, with Kalaris surviving as the wholly-owned subsidiary. The Merger was unanimously approved by The Company's Board. The closing of the Merger is subject to the satisfaction or waiver of various conditions, by each of the parties, at or prior to the closing of the Merger, including, among other things, (i) the approval by AlloVir stockholders of (a) the issuance of shares of AlloVir common stock, which represent more than 20% of the shares of AlloVir common stock outstanding immediately prior to the Merger, to Kalaris stockholders pursuant to the terms of the Merger Agreement and pursuant to Nasdaq Listing Rule 5635(a) and (b) the change of control of AlloVir resulting from the Merger, and (ii) the adoption of the Merger Agreement by the requisite Kalaris stockholders.

If the Company is unable to satisfy certain closing conditions to the Merger Agreement or if other mutual closing conditions to the Merger Agreement are not satisfied, Kalaris will not be obligated to complete the Merger. The Merger Agreement contains certain termination rights of each of AlloVir and Kalaris. Under certain circumstances detailed in the Merger Agreement, the Company could be required to pay Kalaris a termination fee of $3.48 million or Kalaris could be required to pay AlloVir a termination fee of $10.41 million. In addition, in certain circumstances upon the termination of the Merger Agreement, the Company could be required to pay the reasonable costs and expenses of Kalaris in an amount not to exceed $580,000, or Kalaris could be required to pay AlloVir's reasonable costs and expenses in an amount not to exceed $580,000.

Additional Permitted Bridge Financing

Pursuant to the Merger Agreement, Kalaris is permitted to enter into the Additional Permitted Bridge Financing. On January 10, 2025, as a part of the first tranche of the Additional Permitted Bridge Financing, Kalaris issued the AlloVir Note under which the Company funded a principal amount of $3.75 million, and Kalaris issued convertible promissory notes in an aggregate principal amount of $3.75 million to existing Kalaris stockholders (see Note 16). Prior to the closing of the merger, Kalaris has the opportunity to receive an additional $7.5 million in the second tranche of the Additional Permitted Financing of which $3.75 million would be provided by

existing Kalaris stockholders and the remaining $3.75 million would be provided by AlloVir. However, Kalaris no longer expects the second tranche of the Additional Permitted Financing to be funded. Upon the closing of the Merger, the AlloVir Note will be cancelled and the aggregate amount outstanding under the AlloVir Note will be added to the Company's net cash.

Other Obligations

The Company may incur potential contingent payments upon the Company's achievement of clinical, regulatory and commercial milestones, as applicable, or the Company may be required to make royalty payments under license and grant agreements the Company has entered into with various entities pursuant to which the Company has 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 7).