Prurigo nodularis (PN) is a chronic inflammatory disease characterized by chronic pruritus, pruriginous lesions and history or signs of scratching. Numerous studies have highlighted the important role of the microbiome in different skin conditions, but the microbiome composition of PN skin has remained understudied. Here, we aimed to assess the microbial diversity of PN skin and determine its changes accompanying treatment response to the anti-IL-31RA agent nemolizumab.
159 samples from PN patients (32 nemolizumab treated and 35 placebos), at baseline (bl) and week 12 (w12) were included in the study (NCT03181503). Data were processed by MOTHUR, with sequence reads classified into phylum/genus levels. We showed that the Shannon diversity was higher in non-lesional PN samples (p=0.047). Notably, pruritus (measured by Pruritus Numeric Rating Scale; PNRS) had a significant association (beta=0.2, p=0.0018) with Shannon diversity only at w12 in treatments. Furthermore, improvement of PNRS in w12 was significantly associated with (beta=-0.16, p=0.02) change of Shannon diversity in w12 only in treatment group, leading to a significant lower (p=0.014) Shannon diversity in responders (>=4 PNRS improvement from bl) than non-responders in w12. When comparing the phylum expression between bl vs. w12 lesional area, we only observed significant results (e.g., more Campylobacterota and Synergistetes in w12 than bl) in treatments, while no consistent shifts were seen in the placebos. Notably, changes from non-lesional to lesional skin at bl were significantly correlated with the changes between bl vs. w12 only in treatments (rho=-0.65; p-value=0.007). Our results demonstrate that nemolizumab treatment can influence microbiome diversity and is able to reverse the w12 lesional skin microbiome composition to non-lesional skin at bl.

LB059 - Changes in microbiome composition in nemolizumab-treated prurigo nodularis

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.