French healthcare company Sanofi S.A. (Euronext Paris:SAN) (Nasdaq:SNY) reported on Thursday that its experimental antibody amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 trial for patients with moderate-to-severe atopic dermatitis.

The study included adults and adolescents aged 12 and older, with treatment arms dosed every four weeks or every 12 weeks.

At week 24, amlitelimab demonstrated statistically significant and clinically meaningful improvements in skin clearance and disease severity versus placebo, with efficacy continuing to increase during the treatment period. Both US and EU co-primary endpoints were achieved, including validated investigator assessments and EASI-75 scores.

Key secondary endpoints were also met, including reductions in erythema severity and itch intensity. Safety data showed that amlitelimab was well-tolerated, with adverse events largely consistent with placebo and no new safety signals identified.

Sanofi emphasised that amlitelimab could become the first atopic dermatitis therapy requiring as few as four doses per year.

Full trial results will be presented at an upcoming medical meeting, while additional phase 3 studies under the OCEANA program are expected to read out through 2026 to support global regulatory filings.