Sanofi SA, listed as NASDAQ:SNY, recently disclosed results from two global phase 3 clinical trials evaluating the efficacy and safety of amlitelimab, a fully human monoclonal antibody targeting OX40-ligand (OX40L). This agent, engineered to treat moderate-to-severe atopic dermatitis (AD) in individuals 12 years and older, is under consideration as a potential successor to Dupixent, a leading drug for eczema.
The company characterized the presented data set as a comprehensive body of evidence, underscoring amlitelimab’s therapeutic promise for moderate-to-severe AD patients. These phase 3 studies assessed outcomes after 24 weeks of treatment, administering amlitelimab at two dosing intervals: every four weeks (Q4W) and every 12 weeks (Q12W).
Trial Results and Safety Profile
Overall, amlitelimab demonstrated a well-tolerated safety profile in these trials, consistent with prior data. The two phase 3 studies, SHORE and COAST 2, focused on clinically meaningful endpoints, including the proportion of patients achieving substantial improvement in AD symptoms.
SHORE Trial: Positive Outcomes With Background Therapy
The SHORE study enrolled 596 patients who received amlitelimab alongside medium-potency topical corticosteroids (TCS), with or without topical calcineurin inhibitors. Sanofi reported that amlitelimab met all primary and key secondary endpoints compared to placebo plus TCS.
Specifically, significantly higher percentages of patients on amlitelimab administered either Q4W or Q12W reached clear or almost clear skin, as measured by the validated Investigator's Global Assessment for Atopic Dermatitis (vIGA-AD) scores of 0 or 1, compared to placebo recipients. Rates were 28.7% to 32.9% with amlitelimab versus 16.8% with placebo.
Additionally, the proportion achieving at least a 75% improvement in the eczema area and severity index (EASI-75) ranged from 46.8% to 50.9% in treated groups, contrasting with approximately 32.3% to 34.2% in the placebo group. These metrics denote clinically significant amelioration in dermatitis severity.
COAST 2 Trial: Efficacy Demonstrated Amid Statistical Limitations
The COAST 2 trial included 547 patients treated with amlitelimab monotherapy on the same dosing schedules. In the U.S. estimand analysis, the trial met its primary endpoint at Week 24, with non-responder imputation rates of 25.3% and 25.7% for Q4W and Q12W dosing respectively, compared to 14.8% for placebo.
However, in the European (EU) estimand analysis, the co-primary endpoints measuring proportions of patients achieving vIGA-AD 0/1 and EASI-75 did not reach statistical significance versus placebo. Moreover, a key secondary endpoint assessing vIGA-AD 0/1 with barely perceptible erythema also missed significance in the U.S. estimand assessment.
Additional Phase 2 Findings
Sanofi further provided preliminary insights from the ATLANTIS phase 2 trial involving 591 patients. This analysis revealed that amlitelimab delivered progressively improved skin clearance and reduced disease severity continuing beyond 24 weeks, extending up to 52 weeks post-treatment initiation.
Regulatory and Development Outlook
Two additional global phase 3 trials, designated AQUA and ESTUARY, are expected to report data in the latter half of 2026. Supported by the current trial data, Sanofi intends to pursue worldwide regulatory submissions for amlitelimab in the second half of 2026.
Separately, it is noteworthy that in January, the U.S. Food and Drug Administration (FDA) issued a complete response letter regarding Sanofi's new drug application for tolebrutinib targeting non-relapsing secondary progressive multiple sclerosis. The FDA flagged concerns regarding both the efficacy and safety of that candidate, illustrating ongoing regulatory challenges for Sanofi’s pipeline.
Market Reaction
Following the report of trial outcomes, Sanofi’s shares experienced a modest decline, decreasing by 0.37% to close near $46.33 during premarket trading on the reported day, as per Benzinga Pro data.