Real‐life evaluation of mepolizumab efficacy in patients with severe eosinophilic asthma, according to atopic trait and allergic phenotype

Abstract

Background Anti‐interleukin‐5 (IL‐5) monoclonal antibodies can be used as add‐on biological therapies in allergic and non allergic patients with severe eosinophilic asthma. However, within such a therapeutic context real‐life investigations are lacking. Objective Therefore, the aim of the present observational study was to evaluate the effects of mepolizumab in allergic and non allergic subjects with severe eosinophilic asthma. Methods Relevant clinical, functional, laboratory, and pharmacotherapeutic parameters were assessed in the above patient subgroups. Results After one year of add‐on biological treatment with mepolizumab our 88 patients experienced a remarkable improvement of their severe asthma, documented by a better symptom control, expressed by a significant improvement in asthma control test (ACT) score. Indeed, the mean value (± standard deviation) of ACT score increased from 12.55 (± 3.724) to 21.08 (± 3.358). Moreover, significant improvements were also detected with regard to the median values (interquartile range) of forced expiratory volume in one second (FEV₁), blood eosinophil numbers, annual rate of disease exacerbations, and daily intake of oral corticosteroids (OCS). In particular, FEV₁ enhanced from 1640 mL (1110‐2275) to 1920 mL (1525‐2615), blood eosinophil count dropped from 711.0 cells/µL (500.0‐1022) to 90.00 cells/µL (50.00‐117.5), the annual rate of asthma exacerbations decreased from 3.000 (2.000‐6.000) to 0.000 (0.000‐1.000), and the daily prednisone intake fell from 6.250 mg (0.000‐25.00) to 0.000 mg (0.000‐0.000). After one year of mepolizumab treatment, the improvements in clinical, functional and hematological parameters were quite similar in patient subgroups characterized by skin prick test (SPT) negativity or positivity, respectively. A significant correlation was observed between serum IgE levels and OCS intake decrease (r = ‐0.2257; p < 0.05). Conclusion and clinical relevance Hence, our real‐life data suggest that mepolizumab can represent a valid add‐on therapeutic option for patients with severe eosinophilic asthma, irrespective of IgE serum concentrations and allergic sensitization.