Regeneron amends Sanofi collaboration agreement for $1 billion upfront

Regeneron Pharmaceuticals, Inc. (REGN) entered into the Sixth Amendment to its Amended and Restated License and Collaboration Agreement with Sanofi Biotechnology SAS and Sanofi Parent on October 1, 2026, according to a regulatory filing.

Pursuant to the agreement, the parties agreed to co-develop and co-commercialize four new long-acting, Regeneron-invented antibodies targeting IL-13, IL-4, IL-4Rα, and a bispecific antibody targeting IL-4xIL-13. Regeneron also secured options to include Sanofi's Phase 2/3 asset lunsekimig and another early development product on an asset-by-asset basis.

Sanofi will pay Regeneron an upfront payment of $1.0 billion. Regeneron is also entitled to receive up to an additional $7.0 billion in development, regulatory, and commercial milestone payments. Global profits on the new licensed products will be shared equally.

Global development costs will be shared equally by both parties, though development costs exceeding a budget cap for the new products will be the responsibility of Regeneron, subject to future recoupment rights. Regeneron will lead development and regulatory activities prior to filing for marketing approval. Regeneron will remain the lead regulatory party in the United States, while Sanofi will lead regulatory filings outside the United States and commercialization globally.

In connection with the agreement, Regeneron and Sanofi entered into a settlement agreement to dismiss Regeneron's lawsuit concerning access to commercialization information for Dupixent and other products, as well as audit rights.

Separately, Regeneron expects its third-quarter 2026 financial results to include an acquired in-process research and development charge of approximately $22 million on a pre-tax basis. The company said this charge will negatively impact both GAAP and non-GAAP net income per diluted share for the quarter by approximately $0.18.