Material Agreement (Form 8-K)

On September 8, 2026, Amylyx Pharmaceuticals, Inc. (the "Company") entered into a Manufacturing and Supply Agreement (the "Bachem Manufacturing Agreement") with Bachem Americas, Inc. ("Bachem") and on September 1, 2026, the Company entered into a term sheet (the "Polypeptide Term Sheet") with Polypeptide Group AG ("Polypeptide"), pursuant to which Bachem and Polypeptide, respectively, will manufacture and supply the Company's long-term supply requirements of avexitide drug substance for commercial use, if approved. Bachem and Polypeptide will be non-exclusive suppliers and the Company may procure supplies from one or more alternate manufacturers.

Bachem Manufacturing Agreement

Pursuant to the Bachem Manufacturing Agreement, beginning in 2028, the Company has agreed to purchase a minimum quantity of avexitide drug substance per calendar year during the term of the Bachem Manufacturing Agreement at the applicable supply price. Under the Bachem Manufacturing Agreement, the Company will provide periodic estimates of its supply needs to Bachem, a portion of which will be binding upon both parties. The supply price will be adjusted on an annual basis, effective on January 1 of each year, to reflect increases in, among other things, labor, utilities and overhead. The Company will also pay certain other maintenance fees and expenses as contemplated by the Supply Agreement.

The Bachem Manufacturing Agreement has an initial term of five years and will automatically renew for successive three-year periods, unless earlier terminated in accordance with its terms. Either party may terminate the Bachem Manufacturing Agreement upon prior written notice under certain circumstances, including for material breach (subject to specified cure periods) or bankruptcy or insolvency. The Company may also terminate the Bachem Manufacturing Agreement upon certain regulatory actions or objections.

The Bachem Manufacturing Agreement contains customary representations, warranties and covenants, including with respect to the ownership of any intellectual property created pursuant to the Bachem Manufacturing Agreement, as well as provisions relating to acceptance, warranty, quality, testing and inspection, audit, access to information, indemnification, confidentiality and other matters.

Polypeptide Term Sheet

Pursuant to the Polypeptide Term Sheet, the Company and Polypeptide shall negotiate in good faith and promptly enter into a definitive written agreement consistent with the terms set forth in the Polypeptide Term Sheet and other mutually agreeable terms and conditions (the "Polypeptide Manufacturing Agreement"). Under the Term Sheet, the Company will pay a $30 million upfront fee to Polypeptide for capacity reservation and in consideration of the commitments described therein.

Pursuant to the Polypeptide Term Sheet, and subject to the execution of the Polypeptide Manufacturing Agreement, the Company and Polypeptide have agreed, among other things: (i) that beginning in 2028, the Company will purchase a minimum quantity of avexitide drug substance per calendar year during the term of the Polypeptide Manufacturing Agreement at the applicable supply price; (ii) that the Company will provide periodic estimates of its supply needs to Polypeptide, a portion of which will be binding upon both parties, and (iii) to fixed volume-based pricing, as may be adjusted on an annual basis.

The foregoing descriptions of the Bachem Manufacturing Agreement and Polypeptide Term Sheet are qualified in their entirety by reference to the full text of the Bachem Manufacturing Agreement and Polypeptide Term Sheet, respectively, copies of which will be filed as exhibits to the Company's Quarterly Report on Form 10-Q for the fiscal quarter ending September 30, 2026.