Sanofi’s $1.4B Kymab bet falters again as atopic dermatitis trials scrapped

News Drug Development Sanofi’s $1.4B Kymab bet falters again as atopic dermatitis trials scrapped July 24, 2026 | 3 min read | Gabrielle Masson Twitter LinkedIn Facebook Email Print Sanofi had hoped the acquisition of Kymab would fill a major hole that will be left as autoimmune juggernaut Dupixent heads toward a patent cliff. Now, another therapy has failed to meet expectations. Sanofi is scrapping all but one ongoing trial for an autoimmune asset that came from the $1.4 billion acquisition of Kymab after the monoclonal antibody failed to show improvement over the standard of care in atopic dermatitis.“Sanofi has determined that the totality of efficacy and safety evidence generated to date does not support further development of amlitelimab in AD,” the French pharma said in a Thursday press release. Despite significantly reducing skin lesions and disease severity in the Phase 3 COAST-1 study for AD last fall, amlitelimab didn’t show “meaningful improvement” to the current standard of care, Sanofi added.The OX40-ligand antibody was the centerpiece of Sanofi’s $1.4 billion acquisition of immunology biotech Kymab in 2021. But in COAST-1, the candidate remained “meaningfully inferior” to Sanofi’s own immunology blockbuster Dupixent, Leerink Partners wrote at the time. While a long-term extension study demonstrated maintenance of clinical response, it wasn’t enough for Sanofi to keep developing the program. The pharma will now discard the asset in AD “as part of an ongoing strategic assessment of the pipeline.” The drugmaker’s plans to submit the drug for FDA approval in the indication have also gone to the wayside. Previously, the company had planned on filing the drug for AD with regulators sometime in the second half of this year.Analysts at Leerink Partners were not surprised by the discontinuation, writing in a Friday note that “amlitelimab demonstrated modest efficacy and there were two cases of Kaposi’s sarcoma previously reported in clinical trials.” Sanofi confirmed with the analyst that no further cases of Kaposi’s sarcoma had been recorded.No other new pipeline changes have been made alongside the AD termination, a Sanofi spokesperson told BioSpace, adding that the pharma will “share an update on the overall company strategy and focus at a later date.”Beyond COAST-1, Sanofi was running several other AD trials for amlitelimab across the OCEANA clinical development program, which will all be wound down.When asked about the possibility of a workforce reduction tied to the discontinuation, the spokesperson said, “Sanofi is working to identify the best and most appropriate path forward for all staff who have supported the development of amlitelimab in AD.”Sanofi is still running a mid-stage trial of amlitelimab in celiac disease, with a readout slated for the second half of this year. Clinical research Sanofi’s $1.4B Kymab Bet Falters as Asthma Drug Stumbles in Phase II Analysts at Leerink agreed with Sanofi that, despite falling short of statistical significance in the Phase II TIDE-Asthma trial, amlitelimab warrants further development in this indication. April 16, 2025 · 2 min read · Tristan Manalac Read more Aside from celiac disease and AD, Sanofi tested amlitelimab as a potential treatment for hidradenitis suppurativa, alopecia areata, asthma and scleroderma, though the company no longer lists any of these indications in its pipeline for the drug. Previously, the drugmaker touted amlitelimab “as one of its top three pipeline assets, with peak sales potential exceeding €5 billion” ($5.69 billion), according to a 2025 note from Leerink Partners.Despite the discontinuation, Sanofi’s full-year 2026 guidance remains unchanged.“Immunology remains a core strategic pillar of Sanofi including and beyond our cornerstone medicine, Dupixent,” the company’s spokesperson said. “We always follow the science, which means having to sometimes make tough choices. However, this doesn’t distract from our focus of advancing transformative medicines for the patients we serve.”Beyond amlitelimab, Sanofi also picked up monoclonal antibody alomfilimab from the Kymab buy—an asset the company no longer lists in its pipeline. Last year, the Big Pharma discontinued a Phase 1/2 trial of the therapy in patients with advanced malignancies early due to a “strategic sponsor decision,” according to ClinicalTrials.gov. Rare diseases Sanofi cans late-stage study for rare autoimmune disease on underwhelming efficacy The discontinuation of Sanofi’s Phase 3 study for its complement inhibitor drug in chronic inflammatory demyelinating polyneuropathy delivers an ‘obviously disappointing’ blow to the broader drug class, according to William Blair. June 10, 2026 · 2 min read · Tristan Manalac Read more This is the second Sanofi discontinuation in autoimmune due to efficacy concerns to occur this summer, following the termination of a Phase 3 study for a complement inhibitor drug in chronic inflammatory demyelinating polyneuropathy. Announced in June, the decision was made after an interim data analysis found the trial “unlikely to provide sufficient efficacy.”The news also comes amid several leadership shake-ups at Sanofi. Last month, the pharma’s R&D head Houman Ashrafian departed, with Xaira Therapeutics’ Chief Medical Officer Paulo Fontoura expected to take the reins in September. Fontoura will report to CEO Belén Garijo, who succeeded Paul Hudson in April as Sanofi prepares for a major revenue gap expected once Dupixent’s patent expires in 2031. Twitter LinkedIn Facebook Email Print Pipeline Phase 3 Immunology and inflammation Clinical research Sanofi Gabrielle Masson Gabrielle is a senior editor at BioSpace. You can reach her at gabrielle.masson@biospace.com.