Influence of aeroallergen sensitization and nasal polyposis on mepolizumab response in eosinophilic severe asthma.

Background: Studies on the impact of comorbidities on treatment responses in severe eosinophilic asthma (SEA) are limited. This study was a real-world investigation into how the presence or absence of nasal polyps (NP) and sensitivity to aeroallergens influence the outcomes of mepolizumab therapy. Methods: In this retrospective study, data obtained from patients with SEA and who received at least 6 months of mepolizumab treatment were analyzed. The patients were initially divided into two groups based on the presence of NPs. Within these two groups, the patients were further categorized into subgroups according to the presence of aeroallergen sensitivity (AE). Asthma-related outcomes in the resulting four groups were evaluated both before mepolizumab treatment and during the follow-up period. Results: Among the 36 patients with NPs, 14 (38.8%) had AE (NP+AE+), whereas 22 (61.2%) did not (NP+AE-). Of the 35 patients without NPs, 17 (48.5%) had AE (NP-AE+), and 18 (51.5%) did not (NP-AE-). The presence of NPs, independent of AE, was significantly associated with an increase in asthma exacerbations and oral corticosteroid (OCS) use before treatment (p < 0.001). In the NP+AE+ group, the baseline Asthma Control Test (ACT) score was lower, and the number of hospitalizations was significantly higher (p < 0.001). After mepolizumab treatment, all four groups showed significant reductions in asthma-related exacerbations, hospitalizations, and OCS use. Furthermore, ACT scores and pulmonary function test parameters significantly improved. There were limited differences in asthma improvements among the groups, with the NP+AE+ group showing a significant increase in ACT scores and a reduction in hospitalizations compared with the other groups (p < 0.001). Conclusion: Mepolizumab significantly reduced asthma exacerbations, hospitalizations, and OCS use in the patients with SEA with four different phenotypes. Analysis of these findings suggests that mepolizumab provides real-world benefits regardless of the presence or absence of NPs and AE.