Nemolizumab Treatment for Severe Atopic Dermatitis Led to the Simultaneous Improvement of Coexisting Refractory Alopecia Areata: A Case Report

This case report describes a 56-year-old Japanese woman with severe atopic dermatitis (AD) and coexisting refractory alopecia areata (AA) who was treated with nemolizumab, an anti-IL-31 receptor A monoclonal antibody. Despite previous unsuccessful treatments for AA, nemolizumab, administered for AD, led to a 90% improvement in the Eczema Area and Severity Index (EASI) score and a simultaneous decrease in the Severity of Alopecia Tool (SALT) score after 3 months. The report suggests that nemolizumab may suppress the JAK–STAT pathway, potentially improving AA, although its use is only approved for severe AD. This single case highlights the potential benefit of controlling AD activity for managing coexisting AA, though the improvement in AA could be coincidental.