Background/objectives: Itch is the most burdensome symptom in atopic dermatitis (AD) and prurigo nodularis (PN) and is associated with significant psychological distress, sleep deprivation and impaired quality of life. Achieving rapid control of itch is expected to minimize symptomatology and disease burden. Nemolizumab, which targets the interleukin 31 (IL-31) pathway, rapidly relieved itch in Phase 2 trials; thus, a post hoc analysis of four pivotal randomized controlled clinical trials of nemolizumab in AD and PN was performed to further evaluate the improvement of itch over the first 14 days of therapy.
Methods: Data from ARCADIA 1 and 2 in AD (N = 1728) and OLYMPIA 1 and 2 in PN (N = 560) were analysed. Patients reported itch intensity and sleep disturbance daily. Differences in the proportion of itch and sleep responders (patients with ≥4-point improvement from baseline in peak pruritus numerical rating scale [PP-NRS] or sleep disturbance [SD-NRS] score) between nemolizumab and placebo groups were calculated.
Results: Nemolizumab rapidly reduced itch in AD (ARCADIA 1 and 2), with a difference versus placebo in PP-NRS responders apparent by Day 2 (pooled data: 10.7% vs. 2.9%; 95% CI: 5.6-10.1; p < 0.0001) that steadily increased through Day 14. Nemolizumab also reduced itch rapidly in PN (OLYMPIA 1 and 2); a difference versus placebo occurred by Day 2 (pooled data: 17.2% vs. 3.7%; 95% CI: 6.8-16.7; p < 0.0001). Early improvement (Day 2) was also observed in sleep in nemolizumab-treated patients. In pooled analyses in AD, 9.9% (nemolizumab) versus 4.6% (placebo; 95% CI: 2.8-7.7; p = 0.0001) were SD-NRS responders and in PN, 13.4% versus 4.3% (95% CI: 4.0-13.0; p = 0.0013). Itch and sleep response data in individual studies were consistent with the pooled data.
Conclusions: This analysis confirms previously reported data that nemolizumab relieves itch and sleep disturbance by Day 2 in patients with moderate-to-severe AD and PN, indicating that targeting the IL-31 pathway presents an important way to achieve rapid itch response.
Keywords: atopic dermatitis; eczematous disease; interleukin 31; itch; nemolizumab; onset of action; prurigo nodularis; pruritus; sleep disturbance.
People with skin diseases such as atopic dermatitis and prurigo nodularis experience itch, which can be severe and can interfere with their daily lives with missed school or work days and psychological well‐being impairment, especially when the itching lasts for a long time as is often the case with these diseases. Itching can also make it hard to sleep. A medicine that quickly stops itching can help people with atopic dermatitis and prurigo nodularis to feel better. Nemolizumab is a medicine that is approved to treat atopic dermatitis and prurigo nodularis and it works fast to stop itching. This study looked at data from four clinical studies of nemolizumab, focusing on how itch changed during the first 14 days of treatment. Patients in the studies who had atopic dermatitis or prurigo nodularis recorded daily in diaries how much itch they felt and how they slept. The researchers found that nemolizumab started working to control itching in just 2 days and patients also slept better. Less itching and better sleep may improve well‐being in people with atopic dermatitis and prurigo nodularis.
© 2025 The Author(s). Journal of the European Academy of Dermatology and Venereology published by John Wiley & Sons Ltd on behalf of European Academy of Dermatology and Venereology.