3-Year Nemolizumab Data: Early Responders Hit EASI-90 and Lasting Itch Relief

By Tom Whitfield

Roughly 4 in 5 patients with moderate-to-severe atopic dermatitis who responded early to nemolizumab reached EASI-90 by week 152, and half achieved completely clear skin at three years. That's the headline from a post hoc analysis of the ARCADIA long-term extension, presented at the 2026 Fall Clinical Dermatology Conference in Las Vegas, Nevada.

Sarina Berger Elmariah, MD, PhD, MPH, first author of the analysis and director of the UCSF Center of Excellence for Itch and Neurosensory Disorders, reviewed the findings with HCPLive's editorial team.

Nemolizumab (Nemluvio; Galderma) blocks the interleukin (IL)-31 receptor alpha. The replicate phase 3 ARCADIA 1 and ARCADIA 2 trials enrolled 1,728 patients aged 12 years and older, all using concurrent topical therapy. At week 16, more nemolizumab recipients than placebo recipients reached Investigator's Global Assessment (IGA) 0/1 — 36% and 38% versus 25% and 26%, respectively.

Who was followed, and for how long?

The new analysis tracked 295 participants who met response criteria at the close of the 16-week pivotal phase. Response was defined as IGA 0/1 or a 75% improvement on the Eczema Area and Severity Index (EASI-75). All stayed on every-4-week dosing through week 152.

By that endpoint:

• About 4 in 5 had reached EASI-90
• Half had fully clear skin
• Roughly 80% reported being itch-free or nearly itch-free

Elmariah noted that lesion clearance in this group kept deepening instead of leveling off. Results held across the broader extension population too: among 1,903 participants, up to 75% reached EASI-90 and up to 73% were itch-free or nearly itch-free.

What does IL-31 blockade change clinically?

Elmariah described itch as the main reason patients with atopic dermatitis seek care, whatever their disease severity. Dermatologists have historically focused on controlling inflammation first, expecting pruritus to improve afterward.

With IL-31 blockade, that sequence flips. Itch relief tends to come first, and skin clearance builds over months. In practice, Elmariah said, an early response is a reassuring sign the benefit will continue. Patients whose lesions improve slowly can still move toward near or complete clearance if they stay on therapy.

What questions remain?

Elmariah called for mechanistic studies of what suppressing itch does biologically. It could quiet sensory nerves, interrupt inflammatory signaling, or change how immune, nerve, and skin cells communicate. The answers, she argued, could show whether long-term agents support true remission, disease modification, or control of related comorbidities.

Disclosures: Elmariah has received consultancy and advisory board honoraria from Bambusa Therapeutics, Celldex Therapeutics, Disk Medicine, Galderma, Genzyme, Incyte, Novartis, Pfizer, Regeneron, Sanofi, and ZenZema.

With clearance still deepening at three years and no plateau in sight in this responder cohort, longer follow-up and mechanistic work will determine whether IL-31 blockade can deliver disease modification rather than symptom control alone.