Sanofi and Regeneron bring four new long acting antibodies into Dupixent partnership in deal worth up to $8 billion

Sanofi will pay Regeneron Pharmaceuticals $1 billion upfront to gain a stake in a batch of new long acting immunology antibodies, with up to $7 billion more payable if development, regulatory and sales milestones are met. The agreement extends a partnership that began in 2003 and produced Dupixent (dupilumab), now the leading treatment worldwide for diseases driven by type 2 inflammation. More than 1.5 million patients currently use Dupixent across nine approved indications, placing it among the most widely used antibody medicines in the world.

The new deal covers four antibodies discovered by Regeneron. They act on interleukin 13 (IL-13), interleukin 4 (IL-4), the interleukin 4 receptor alpha (IL-4Rα), and a bispecific that hits both IL-4 and IL-13. The furthest advanced, an IL-13 antibody called REGN20423, is being tested in a Phase 1 study in atopic dermatitis. The remaining three should reach the clinic in 2027. Regeneron has also secured an option to add lunsekimig, Sanofi’s experimental bispecific Nanobody® VHH therapy directed at TSLP and IL-13, once Phase 3 trials in chronic obstructive pulmonary disease wrap up.

On the commercial side, Regeneron will run research and development, and Sanofi will take charge of selling any resulting products around the world. Costs will be split evenly between the companies, and so will any profits that follow. Terms governing Dupixent itself remain unchanged.

Belén Garijo, chief executive officer of Sanofi, called the agreement a deliberate first step towards restarting the company’s innovation engine. She said the partnership with Regeneron has reshaped care for millions of people with type 2 inflammatory conditions and built one of the strongest immunology franchises anywhere, and that closer cooperation should speed up the arrival of new treatments for immune mediated disease while supporting Sanofi’s long term outlook.

Leonard S. Schleifer, MD, PhD, board co-chair, president and chief executive officer at Regeneron, said few alliances in biopharma have been as productive as this one. He said the expanded agreement should help the next generation of immunology medicines reach patients sooner, and that the new antibodies are now set up to achieve the sort of fast, global reach Dupixent has already shown.

George D. Yancopoulos, MD, PhD, board co-chair, president and chief scientific officer at Regeneron and a principal inventor of Dupixent, pointed out that the two companies have been working together since 2003 and have brought several medicines to market. He said Dupixent changed the standard of care for type 2 inflammatory disease and has become one of the most widely used antibodies for any condition, and that pairing Regeneron’s discovery and antibody engineering strengths with Sanofi’s global reach gives both companies a chance to deliver another wave of progress in immunology.

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Related Topics and Keywords

Dupixent, Regeneron, Sanofi