Real-Life Performance of Mepolizumab in T2-High Severe Refractory Asthma with the Overlapping Eosinophilic-Allergic Phenotype

Severe asthma (SA) is categorized into multiple overlapping phenotypes and clinical characteristics driven by complex mechanistic inflammatory pathways. Mepolizumab is a human monoclonal antibody effectively targeting interleukin-5 in severe eosinophilic asthma. However, the eligibility of biologics in coincident SA phenotypes is still unclear. We assessed the efficacy and safety of mepolizumab in real-life patients with the overlapping T2-high SA endotype. This was a phase IV, single-centre observational cohort study including patients with severe refractory T2-high asthma in treatment with mepolizumab. After 12 months of treatment with mepolizumab, significant improvements (p < 0.0001) in asthma control and lung function were recorded. Rates of clinically significant annual asthma exacerbation were also decreased by 71.22% after 52-week therapy with mepolizumab (p < 0.001) associated with a reduction in the mean daily dose of oral corticosteroids. Two patients (3.27%) had to discontinue mepolizumab due to musculoskeletal disorders with no severe safety issues reported. The use of mepolizumab as an add-on therapy in routine clinical practice was safely associated with significant clinical and functional in the overlapping eosinophilic-and-allergic SA phenotype. The current data should support clinical and therapeutic decision-making in this T2-high SA endotype.