Long-term treatment matters enormously in atopic dermatitis. A medicine may work well during the first few months, but atopic dermatitis is usually a chronic disease. Patients and clinicians therefore need to know whether benefits can continue — and whether new safety concerns appear — after years of treatment.
New data presented around the 2026 EADV Congress provide a longer view of nemolizumab, marketed as Nemluvio.
Galderma reported three-year findings from the »ARCADIA long-term extension study«, which follows adults and adolescents aged 12 years and older with moderate-to-severe atopic dermatitis. The extension study evaluates nemolizumab for up to 200 weeks. At Week 152, Galderma reported sustained improvements across several outcomes important to people living with atopic dermatitis.
In observed-case analyses, up to 91% of participants achieved at least a 75% improvement in disease severity, measured by EASI-75. Up to 75% achieved EASI-90, representing at least a 90% improvement. Up to 67% reached clear or almost-clear skin according to the Investigator Global Assessment.
But the results are particularly interesting because they look beyond visible skin lesions. Nemolizumab targets the IL-31 receptor alpha pathway, which is strongly associated with itch. At Week 152, up to 88% of participants achieved a clinically meaningful reduction in itch, while up to 73% reached an itch-free or nearly itch-free state, according to Galderma. Quality of life also improved, with up to 92% reaching clinically meaningful improvement on dermatology-related quality-of-life measures.
Sleep is especially relevant. For many people with moderate-to-severe atopic dermatitis, night-time itch is one of the most disruptive parts of the disease. Scratching can repeatedly wake patients, resulting in exhaustion, concentration problems and emotional strain the following day.
Safety is the other major question in long-term extension studies. Galderma reported that nemolizumab remained well tolerated and that its safety profile through three years was consistent with previous findings, with no new safety signals identified.
Long-term extension studies do have limitations. Patients who continue into extensions can differ from those who discontinue earlier, and observed-case analyses only include participants with available data.
Still, three-year information adds something short registration trials cannot provide: evidence about what sustained treatment may look like.
Patients do not only want a medicine that works at Week 16. For a chronic disease, the more meaningful question is whether treatment can keep working through Year 1, Year 2, Year 3 — and beyond.