Werewolf Therapeutics, Inc.

Because this Quarterly Report on Form 10-Q is being filed within four business days from the date of a reportable event, we have elected to make the following disclosure in this Quarterly Report on Form 10-Q instead of in a Current Report on Form 8-K under Items 1.01, 1.02 and 2.01.

On May 6, 2026 (the “Closing”), the Company entered into an asset purchase agreement (the “Purchase Agreement”) with Jazz Pharmaceuticals Ireland Limited, a corporation organized under the laws of Ireland (“Jazz”). In April 2022, the Company entered into a global collaboration and license agreement (the “Collaboration Agreement”) with Jazz under which Jazz acquired exclusive global development and commercialization rights to JZP898, as well as products containing certain isolated recombinant polypeptides comprising IFNα that meet specified criteria (each such product, a Licensed Product). Subject to the terms and conditions of the Purchase Agreement, the Company sold to Jazz (the “Asset Sale”) its program (the “898 Program”) for the development, manufacturing, commercialization, use and other exploitation of the Licensed Product. Pursuant to the Purchase Agreement and related ancillary agreements, in consideration for the Transferred Assets, Jazz paid to the Company upfront consideration of $21.0 million, and has agreed to pay an additional $2.0 million upon the consent to the partial assignment a certain license agreement, as and to the extent such agreement relates to the conduct of the 898 Program. Jazz also assumed certain liabilities of the Company relating to the 898 Program arising after the Closing.

The Purchase Agreement contains customary representations, warranties and covenants of each of the Company and Jazz. The Purchase Agreement further provides that, subject to certain limitations, the Company and Jazz will each indemnify the other for certain losses arising from such breaches of representations, warranties and covenants and liabilities allocated to such party pursuant to the terms of the Purchase Agreement.

In addition, the Purchase Agreement contains a non-competition covenant pursuant to which the Company agreed not to exploit any IFNα or variant thereof, or any product containing any IFNα or variant thereof, for a period of eighteen (18) months after the Closing, subject to customary exceptions for change of control transactions.

The foregoing description of the terms of the Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the terms and conditions of the Purchase Agreement, a copy of which the Company intends to file as an exhibit to its Quarterly Report on Form 10-Q for the quarter ending June 30, 2026.

On May 6, 2026, the Company entered into a letter agreement providing for the repayment by the Company of all amounts owed under the loan and security agreement, dated May 2, 2024 (the “K2HV Loan Agreement”), by and among the Company, the lenders from time to time party hereto (collectively, “Lenders”, and each, a “Lender”), K2 HealthVentures LLC (“K2HV”), as administrative agent for Lenders (in such capacity, together with its successors, “Administrative Agent”), and ANKURA TRUST COMPANY, LLC, as collateral trustee for Secured Parties (in such capacity, together with its successors, “Collateral Trustee”). On May 6, 2026, upon payment by the Company of approximately $31.4 million, all of the Company’s indebtedness and obligations to the Collateral Trustee and the Lenders under the Loan Agreement and any other related loan and collateral security documents was deemed paid and discharged in full.

Lease Termination

On May 7, 2026, the Company entered into an Agreement for Termination of Lease and Voluntary Surrender of Premises (the “Lease Termination”) with ARE-770/784/790 Memorial Drive, LLC (the “Landlord”), pursuant to which the Company and Landlord agreed to terminate that certain the lease, dated June 1, 2021, as amended, by and between the Company and the Landlord (the “Lease”), effective October 31, 2026 or such sooner date as a party provides notices in accordance with the Lease Termination (the “Lease Termination Date”). Under the Lease, the Company leased approximately 25,778 square feet of space, consisting of the entire building located at 200 Talcott Avenue, Watertown, Massachusetts. Pursuant to the Lease Termination, the Company will pay the Landlord an aggregate termination fee of $2.7 million, which shall represent full satisfaction of all remaining payments and other financial obligations due from the Company to Landlord under the Lease including, without limitation, Base Rent (as defined in the Lease) for the months of May 2026 through October 2026. The Company will have no further rent obligations to the Landlord pursuant to the Lease after the Lease Termination Date.

The foregoing description of the terms of the Lease Termination does not purport to be complete and is qualified in its entirety by reference to the terms and conditions of the Lease Termination, a copy of which the Company intends to file as an exhibit to our Quarterly Report on Form 10-Q for the quarter ending June 30, 2026.