Material Agreement, Financial Obligation (Form 8-K)

Item 1.01 Entry into a Material Definitive Agreement.

As previously announced, on December 10, 2025, Sarepta Therapeutics, Inc. (the "Company") entered into separate, privately negotiated exchange agreements (the "Exchange Agreements") with certain holders of its 1.25% Convertible Senior Notes due 2027 (the "Existing Convertible Notes"), including the Michael A. Chambers Living Trust, an entity affiliated with Michael Chambers, a member of the Company's board of directors. Under the terms of the Exchange Agreements, the holders party thereto agreed to exchange with the Company approximately $291.4 million in aggregate principal amount of Existing Convertible Notes held by them for consideration consisting of (i) approximately $291.4 million in aggregate principal amount of 4.875% Convertible Senior Notes due 2030 (the "New Convertible Notes") and (ii) an aggregate of approximately $31.6 million in cash.

The New Convertible Notes were issued by the Company on December 18, 2025 pursuant to an Indenture, dated as of August 28, 2025 (the "Indenture"), as supplemented by the First Supplemental Indenture (the "First Supplemental Indenture"), dated as of December 18, 2025, each between the Company and U.S. Bank Trust Company, National Association, as trustee. The New Convertible Notes constitute "additional Notes" under the Indenture and were issued with the same terms and as part of the same series as the approximately $602.0 million of 4.875% Convertible Senior Notes due 2030 issued in August 2025, as described in the Company's Current Report on Form 8-Kfiled on August 29, 2025. Following the closing of the Exchange, the aggregate principal amount of the Company's 4.875% Convertible Senior Notes due 2030 totals approximately $893.4 million.

The foregoing description of the First Supplemental Indenture, the Indenture and the New Convertible Notes does not purport to be complete and is qualified in its entirety by reference to the First Supplemental Indenture, which is filed as Exhibit 4.1 to this Current Report on Form 8-K,and the Indenture and form of Note, which were filed as Exhibits 4.1 and 4.2 to the Company's Current Report on Form 8-Kfiled on August 29, 2025, and are incorporated herein by reference.

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-BalanceSheet Arrangement of a Registrant

The information set forth under Item 1.01 of this Current Report on Form 8-Kis incorporated herein by reference.