Therapeutic Efficacy of Anti-Interleukin-5 Monoclonal Antibodies in Kimura Disease: A Systematic Review.

Kimura disease (KD) is a rare, chronic inflammatory disorder characterized by painless subcutaneous tumors and lymphadenopathy, predominantly affecting the head and neck region. Its pathogenesis involves a dysregulated T-helper 2 (Th2) immune response leading to lymphoid hyperplasia and eosinophilic infiltration. As interleukin-5 (IL-5) is the cytokine responsible for eosinophil proliferation and survival, anti-IL-5 therapy may be biologically justified in KD. This study aims to investigate the efficacy of benralizumab, reslizumab, and mepolizumab in the treatment of KD. A systematic review following PRISMA guidelines was performed. Although a comprehensive literature search was performed, no published studies or case reports evaluating reslizumab in KD were identified. Nine case reports (11 patients, mean age 36.5 years, one patient received both agents sequentially) were studied regarding benralizumab and mepolizumab. Data extracted included the used agent, previous and concurrent therapy, efficacy, adverse effects, and recurrence. Mepolizumab showed a therapeutic response in seven out of nine cases, including three complete and four partial responses. Benralizumab showed clinical benefit in all treated patients, although one required salvage surgery. However, these findings must be interpreted with caution due to the limited sample size. Clinical improvement enabled the tapering or discontinuation of concomitant immunosuppressing therapy in most responders. No drug-related adverse events were reported over mean treatment durations of 16 months (median 14 months) for mepolizumab and 23 months (median 12 months) for benralizumab. However, cases included in this study may underreport potential long-term or rare adverse effects. Anti-IL-5 agents offer a potential treatment strategy for refractory or recurrent KD, demonstrating efficacy in tumor reduction and a favorable safety profile. These biologics are a corticosteroid-sparing alternative for resistant cases. Current evidence is limited by the reliance on small, heterogeneous case series. Multicenter prospective registries or international collaborative cohorts are required to validate these findings and standardize dosing regimens.