Regeneron Expands Sanofi Collaboration with $1.0B Upfront and up to $7.0B in Milestones

Executive Summary

On October 1, 2026, Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) entered into the Sixth Amendment to its Amended and Restated License and Collaboration Agreement (Antibody LCA) with Sanofi. Under the expanded collaboration, the companies will co-develop and co-commercialize four new long-acting, Regeneron-invented antibody programs. The amendment involves a $1.0 billion upfront payment to Regeneron and eligibility for up to $7.0 billion in milestone payments, alongside a full settlement of outstanding litigation regarding Dupixent®.

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Key Agreement Details (Item 1.01)

• Assets Included: Four novel Regeneron-invented antibodies:
  1. Anti-IL-13 antibody
  2. Anti-IL-4 antibody
  3. Anti-IL-4 receptor alpha (IL-4Rα) antibody
  4. Bispecific anti-IL-4 x IL-13 antibody
• Option Assets: Regeneron holds an option to opt into Sanofi's Phase 2/3 asset lunsekimig (bispecific Nanobody targeting TSLP and IL-13) and an additional early-stage Sanofi program following the completion of certain ongoing trials, subject to cost reimbursement.
• Financial Terms:
  • Upfront Cash: Sanofi will pay $1.0 billion to Regeneron.
  • Milestone Potential: Up to $7.0 billion in aggregate development, regulatory, and commercial milestones.
  • Profit Sharing: 50/50 global profit split on sales of the New Licensed Products.
• Operational & Regulatory Roles:
  • Development costs will be shared equally (subject to budget caps where excess costs are borne by Regeneron with recoupment mechanisms).
  • Regeneron serves as the lead development and regulatory party pre-marketing approval filings globally, and will lead U.S. regulatory filings/commercialization.
  • Sanofi serves as the lead regulatory party ex-U.S. and lead commercialization party globally.

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Litigation Settlement (Item 8.01)

In tandem with the amendment, Regeneron and Sanofi entered into a settlement agreement under which Regeneron agreed to dismiss its pending lawsuit against Sanofi regarding audit rights and commercialization information access relating to Dupixent® (dupilumab) and other collaboration therapies.

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Preliminary Q3 2026 Financial Impact (Item 2.02)

• Acquired IPR&D: Regeneron expects to record a pre-tax acquired in-process R&D charge of approximately $22 million for Q3 2026.
• EPS Impact: The charge is anticipated to reduce GAAP and non-GAAP net income per diluted share by approximately $0.18.