Long-Term Data on Nemolizumab Demonstrate Safety, Sustained Symptom Improvement in Patients With Atopic Dermatitis up to 2 Years

Late-breaking interim 2-year data from a 5-year open-label extension study of nemolizumab (Nemluvio; Galderma) in adults and adolescents with moderate-to-severe atopic dermatitis (AD) demonstrated sustained efficacy and consistent safety through 104 weeks of treatment, with 62.6% of previously treated participants and 58.2% of treatment-naïve participants achieving clear or almost clear skin.1

Further, nearly 90% of nemolizumab-experienced participants and 82% of nemolizumab-naïve participants showed clinically meaningful itch improvement. Most achieved an itch-free or nearly-itch free state, according to the findings announced at Revolutionizing Atopic Dermatitis 2025, held June 6-7, in Nashville, TN.1

Jonathan Silverberg, MD, PhD, MPH

“The relentless itch of atopic dermatitis is not just a symptom; it's a constant burden that disrupts sleep, concentration, and the simple joys of life. Nemolizumab has demonstrated its impact on both itch and skin lesions in atopic dermatitis extensively over the years, and these new data, demonstrating its benefit up to 2 years, add another layer of confidence to that,” ARCADIA lead author Jonathan Silverberg, MD, PhD, MPH, associate professor of dermatology at the George Washington University School of Medicine and Health Sciences in Washington, DC, said in a statement.2

The ARCADIA long-term extension study is the most comprehensive evaluation to date of nemolizumab, an interleukin (IL)-31 receptor antagonist that targets the cytokine pathway central to atopic dermatitis-associated pruritus. Silverberg and colleagues designed this prospective, multicenter, open-label study to evaluate the medication’s long-term safety up to 5 years in individuals aged 12 years and older with moderate-to-severe AD who had completed initial or maintenance period in the phase 3 ARCADIA 1 and 2 trials, a previous phase 2/3 study, or newly enrolled adolescents aged 12 years and older meeting specific disease severity criteria.

The researchers categorized the 1901 participants as either nemolizumab-previously experienced (n=1,164) and nemolizumab-naïve (n=737), the latter group including those from placebo arms of previous studies and the newly enrolled adolescents. All participants received subcutaneous nemolizumab 30 mg every 4 weeks per labeling plus topical corticosteroids or calcineurin inhibitors as background therapy.1

The mean age of participants was 34.4 years in the experienced group and 33.3 years in the naïve group. At baseline, the previously experienced cohort showed less severe disease, with mean Eczema Area and Severity Index (EASI) scores of 11.9 compared to 15.6 in naïve patients, and lower rates of moderate-to-severe disease by Investigator's Global Assessment (IGA) assessment as well (43.9% vs 57.1%, respectively), according to the study.1

FINDINGS

EASI-75 and IGA. Silverberg and colleagues reported sustained improvement in efficacy outcomes across multiple measures through 104 weeks. EASI-75 response rates reached 85.4% in previously experienced participants and 82.2% in naïve patients. Clear or almost clear skin, defined as IGA 0/1, occurred in 62.6% and 58.2% of experienced and naïve participants, respectively. The investigators noted convergence of response rates between the 2 groups over time, suggesting that participants originally naïve to nemolizumab achieved similar benefit levels as those with prior nemolizumab exposure.1

Pruritis, Sleep. Pruritus responses were particularly robust, with 89.1% of experienced and 82.0% of naïve participants achieving 4-point or greater improvements in SCORing atopic dermatitis (SCORAD) VAS pruritus scores, according to the findings. Most participants across the 2 treatment groups reached an itch-free or nearly itch-free state, defined as SCORAD VAS pruritus less than 2, with rates of 75.9% and 67.0% among nemolizumab-experienced and -naïve participants respectively. Sleep disturbance also improved significantly, with 4 point or greater improvements in SCORAD VAS sleep loss scores recorded among 86.7% of experienced and 78.4% of naïve participants.1

Quality of life. Quality of life measures reflected the clinical improvements, with substantial proportions of participants achieving clinically meaningful Dermatology Life Quality Index reductions and scores indicating minimal life impact. The data showed consistent maintenance of these benefits throughout the 2-year observation period.1

Safety. Safety analysis across 3,855.3 person-years of exposure revealed a profile consistent with previous phase 3 studies. Researchers reported treatment-emergent adverse events (TEAEs) in 79.4% of across the 2 cohorts. Most were categorized as mild to moderate infections including nasopharyngitis (19.5%), upper respiratory tract infections (12.7%), and COVID-19. Silverberg et al reported serious AEs in 8.1%, with less than 1% considered related to the study drug. Adverse events leading to study discontinuation occurred in 4.7% of participants and there were no deaths attributed to treatment.1

Silverberg et al emphasized that the convergence of response rates in naïve patients with those of experienced patients over time support nemolizumab’s consistent therapeutic benefit regardless of prior exposure. The long-term safety profile aligned with findings from pivotal phase 3 trials, with no new safety signals emerging during extended treatment.1,2

Nemolizumab was approved by the FDA in August 2024 for the treatment of adults with prurigo nodularis and in December 2024 for the treatment of patients 12 years and older with moderate-to-severe atopic dermatitis, in combination with topical corticosteroids and/or calcineurin inhibitors when the disease is not adequately controlled with topical prescription therapies.3

1. Silverberg JI, Laquer VT, Stein-Gold L, et al. Nemolizumab long-term safety and efficacy up to 104 weeks in the ARCADIA open-label extension study in adolescents and adults with moderate-to-severe atopic dermatitis. Poster presented at: Revolutionizing Atopic Dermatitis 2025; June 6-7, 2025; Nashville, TN.

2. RAD 2025: Long-term data on Nemluvio® (nemolizumab) demonstrate its favorable safety profile and sustained and increased improvements in itch and skin lesions in patients with atopic dermatitis up to two years. News release. Galderma. June 6, 2025. Accessed June 9, 2025. https://www.galderma.com/news/rad-2025-nemluvio

3. Nemluvio US Prescribing Information. Galderma. Accessed June 9, 2025. Available online. Accessed May 2025