Mepolizumab in Pediatric Severe Eosinophilic Asthma: A Review of Efficacy, Safety, and Clinical Applications.

This review aims to critically summarize current evidence on the biological rationale, efficacy, safety, patient selection, and clinical positioning of mepolizumab in children and adolescents with severe eosinophilic asthma. Severe eosinophilic asthma in childhood is associated with recurrent exacerbations, impaired quality of life, healthcare utilization, and cumulative corticosteroid toxicity. Mepolizumab is a humanized monoclonal antibody targeting interleukin-5 and is approved as add-on treatment for severe eosinophilic asthma in children aged 6 years and older. Pediatric pharmacokinetic and pharmacodynamic studies demonstrate profound and sustained suppression of blood eosinophils, while randomized and real-world evidence consistently supports a reduction in severe exacerbations. Available data also suggest corticosteroid-sparing effects and reduced healthcare utilization in selected patients, whereas improvements in lung function and daily symptom control are less consistent. Pediatric studies indicate a generally favorable safety and tolerability profile, although long-term pediatric-specific data remain limited. Within the current biologic treatment landscape, mepolizumab appears particularly relevant when eosinophilic inflammation, recurrent exacerbations, and corticosteroid burden represent the dominant treatable traits. However, the pediatric evidence base remains substantially smaller than that available in adults, and no head-to-head trials have directly compared mepolizumab with other biologics. Important unresolved issues include the identification of more precise predictors of response, the optimal duration of treatment, criteria for treatment withdrawal or switching, and the potential disease-modifying effects of early biologic intervention.