The mixed data from the Phase III COAST 2 trial follows an underwhelming data drop from COAST 1 in September that Leerink Partners said “fell well below expectations.”
While Sanofi’s anti-OX40L antibody amlitelimab significantly eased disease severity in a late-stage eczema study, the asset missed key supporting endpoints, raising questions regarding its overall clinical profile.
Still, banking on the positive signals of efficacy thus far, Sanofi is pushing forward with an approval application for amlitelimab, planned for the second half of this year.
These mixed results, revealed Friday, come after an underwhelming data drop in September last year. At the time, Sanofi claimed victory in the Phase III COAST 1 study, with amlitelimab acing both its primary and secondary endpoints. Analysts, however, were disappointed by the results, with Leerink Partners saying in a Sept. 4 note that the antibody’s performance fell “well below expectations.”
Analysts used Dupixent—which Sanofi co-owns with Regeneron—as a standard. “The magnitude of benefit with amlitelimab came in well below investor expectations . . . compared to approved benchmarks including Dupixent,” William Blair said.
Now, the pharma has released additional late-stage data for amlitelimab, this time from the COAST 2 trial, in which amlitelimab was dosed either once every four or 12 weeks. The primary outcome was the proportion of patients scoring 0 or 1 on a scale called vIGA-AD, which measures disease severity.
Results for the U.S. analysis showed that 25.3% of patients dosed once every four weeks hit the primary endpoint, as did 25.7% of those treated once every 12 weeks. Only 14.8% of placebo comparators hit the primary efficacy bar, according to Friday’s release.
Significantly more patients on both amlitelimab doses showed significantly greater improvement in disease severity as measured by the EASI-75 standard versus placebo.
However, the U.S. analysis failed a key secondary measure, the proportion of patients who achieved vIGA-AD 0/1 while also achieving clearer skin. An analysis of COAST 2 for the European failed the primary endpoint, with amlitelimab unable to statistically outperform placebo at easing disease severity.
Sanofi on Thursday also released data from the Phase III SHORE study, which combined amlitelimab with topical therapies. The trial met all primary and key secondary outcomes, helping build the pharma’s confidence in amlitelimab’s overall profile and supporting a submission in the back half of this year.
Sanofi is also running the Phase II open-label ATLANTIS study and the late-stage AQUA and ESTUARY studies, with data expected later this year, according to Friday’s release.
