Sanofi and Regeneron Expand 20-Year Alliance With $1 Billion Deal for Long-Acting Immunology Antibodies
The Sanofi Regeneron deal has expanded the pharmaceutical companies’ more than 20-year collaboration, with Sanofi agreeing to pay Regeneron $1 billion upfront to develop and commercialize a new group of long-acting immunology antibodies.
The expanded agreement covers four Regeneron-invented antibody programs targeting interleukin-13 (IL-13), an IL-4xIL-13 bispecific, interleukin-4 (IL-4) and interleukin-4 receptor alpha (IL-4Rα). Regeneron could also receive up to another $7 billion in development, regulatory and commercial milestone payments.
The agreement builds on the companies’ long-running collaboration behind Dupixent (dupilumab), one of the most widely used antibody medicines for diseases driven by type 2 inflammation.
Sanofi to Pay $1 Billion Upfront
Under the expanded agreement, Regeneron will receive a $1 billion upfront payment from Sanofi. The deal also includes the possibility of up to $7 billion in additional milestone payments tied to development, regulatory and commercial achievements.
Sanofi and Regeneron will share development and commercialization costs for the new programs equally. Any future profits generated by the products covered by the expanded agreement will also be split 50:50 globally.
Regeneron will lead research and development activities, while Sanofi will take the lead on global commercial efforts.
Four New Long-Acting Antibody Programs
The expanded alliance includes four long-acting antibodies developed by Regeneron.
The programs target different components of the type 2 inflammation pathway:
- REGN20423, a long-acting IL-13 monoclonal antibody
- A long-acting IL-4xIL-13 bispecific antibody
- A long-acting IL-4 antibody
- A long-acting IL-4Rα antibody
REGN20423 is already in a Phase 1 clinical trial for atopic dermatitis. The other three antibody programs are expected to enter clinical studies in 2027.
Because these candidates are still being evaluated, their safety and effectiveness have not yet been established for approved medical use.
Regeneron’s Long-Acting Immunology Strategy
The new agreement follows Regeneron’s previously disclosed strategy of developing next-generation treatments that could potentially provide longer dosing intervals and new approaches to inflammatory diseases.
The company had identified long-acting IL-4, IL-13 and IL-4Rα antibodies, as well as an IL-4xIL-13 bispecific, as part of its next-generation immunology pipeline.
Longer-acting medicines can potentially reduce how frequently patients need to receive treatment. However, the eventual dosing schedules and clinical benefits of these particular candidates will depend on the results of ongoing and future clinical trials.
Dupixent Remains the Foundation
The Sanofi Regeneron alliance dates back more than two decades and has produced multiple approved medicines, most notably Dupixent.
According to the companies, more than 1.5 million people are currently receiving Dupixent across nine indications. The drug targets pathways involved in type 2 inflammation and has become a major product for both companies.
The new agreement is designed to extend the collaboration into the next generation of immunology treatments rather than replace the existing commercial relationship around Dupixent.
Importantly, the companies said the existing profit-sharing agreement for Dupixent will not change under the expanded arrangement.
Potential Addition of Lunsekimig
The agreement also gives Regeneron an option to include lunsekimig, an investigational bispecific Nanobody VHH therapy developed by Sanofi.
Lunsekimig targets TSLP and IL-13 and is being studied for chronic obstructive pulmonary disease (COPD). Regeneron’s option can be exercised after completion of Sanofi’s Phase 3 trials for the medicine.
This provision could further broaden the scope of the companies’ collaboration if the relevant clinical and development conditions are met.
Companies Combine Research and Commercial Capabilities
The expanded partnership brings together Regeneron’s antibody discovery and development capabilities with Sanofi’s global commercial infrastructure.
Under the agreement, Regeneron will remain responsible for research and development activities, while Sanofi will lead global commercialization. Both companies will share development and commercialization expenses for the newly included programs.
The structure is intended to keep the companies aligned on the development and potential global launch of the next-generation medicines.
Previous Collaboration-Related Litigation Settled
As part of the expanded agreement, Sanofi and Regeneron have also settled their previous collaboration-related litigation.
The settlement accompanies the new arrangement and allows the companies to move forward with the expanded antibody partnership.
Neither company disclosed additional financial terms related specifically to the litigation settlement in the announcement.
What the Deal Means for the Biopharma Pipeline
The Sanofi Regeneron deal represents a significant expansion of a collaboration that has already produced a major immunology franchise.
The new programs focus on targets that are closely connected to the biology underlying type 2 inflammatory diseases. By adding multiple long-acting candidates, the companies are pursuing potential treatments that could eventually offer different therapeutic approaches or dosing options.
However, the financial value attached to the agreement should not be interpreted as a guarantee that the medicines will reach the market. Several of the candidates are still in early-stage development, and clinical, regulatory and commercial milestones remain ahead.
A Long-Term Bet on Immunology
For Sanofi and Regeneron, the expanded agreement provides a framework for continued investment in immunology beyond the current generation of medicines.
Regeneron said the alliance has resulted in multiple approved medicines since the collaboration began in 2003, while Sanofi described the expansion as part of its longer-term effort to build its immunology pipeline.
The next major milestones will include clinical development of REGN20423 and the advancement of the other three antibody candidates toward human trials in 2027.
FAQs
1. What is the Sanofi Regeneron deal?
It is an expanded global collaboration between Sanofi and Regeneron covering the development and commercialization of multiple next-generation, long-acting immunology antibodies.
2. How much is Sanofi paying Regeneron upfront?
Sanofi will pay Regeneron $1 billion upfront under the expanded agreement.
3. How much could Regeneron receive in additional payments?
Regeneron could receive up to another $7 billion through development, regulatory and commercial milestone payments.
4. How many new antibody programs are included?
The expanded agreement covers four new long-acting Regeneron-invented antibodies targeting IL-13, IL-4xIL-13, IL-4 and IL-4Rα.
5. What is REGN20423?
REGN20423 is a long-acting IL-13 monoclonal antibody developed by Regeneron. It is currently being studied in a Phase 1 trial for atopic dermatitis.
6. When will the other antibody programs enter clinical trials?
Regeneron and Sanofi expect the other three newly included antibody programs to enter clinical studies in 2027.
7. What is the connection between the deal and Dupixent?
The expanded agreement builds on the companies’ long-standing collaboration that developed and commercialized Dupixent. The existing Dupixent profit-sharing arrangement will remain unchanged.
8. How will the companies divide future profits?
Sanofi and Regeneron will share future profits from the new products 50:50 globally, while also equally sharing development and commercialization costs.
9. Who will lead research and development?
Regeneron will lead research and development activities for the new programs, while Sanofi will lead global commercial efforts.
10. Could Sanofi’s lunsekimig become part of the alliance?
Yes. Regeneron has an option to include Sanofi’s investigational lunsekimig in the collaboration after completion of its Phase 3 COPD trials, subject to the terms of the agreement.
