Predictors of new-onset EGPA in patient with severe asthma treated with anti IL-4/13

<bold>Introduction:</bold> Treatment with anti IL-4/13 (Dupilumab) in patients with severe asthma can be linked with transient blood hypereosinophilia, mostly not associated with significant clinical changes. A small percentage of these patients may develop Eosinophilic Granulomatosis with Polyangiitis (EGPA), a multisystem inflammatory disease characterized by bronchial asthma, eosinophilia, and necrotizing vasculitis of small and medium vessels. <bold>Objective:</bold> The aim of the study is to identify clinical, functional or biohumoral predictive factors of EGPA in a cohort of patients with severe asthma treated with Dupilumab. <bold>Methods:</bold> 50 consecutive outpatients were included in this restrospective study. Clinical, functional, and biohumoral data were collected. Patients were divided into 2 groups according to the occurrence of EGPA after the beginning of treatment. Two-tailed Student t-test or Mann-Whitney U test were used to compare continuous variables. Categorical variables were compared with Fisher’s exact test. Significance was set at 0.05. <bold>Results:</bold> 3 patients (6%) developed EGPA during the follow-up in an average time of 17 (standard deviation =13) months. The maximum historical value of blood eosinophils was significantly higher in EGPA group (1687 vs. 761 cells/microl, p=0.04). Blood eosinophils count at baseline and the other clinical, functional, and biohumoral variables tested were not significantly different in the two groups. <bold>Conclusions:</bold> 6% of patients treated with Dupilumab developed EGPA. The maximum historical value of blood eosinophils could be able to predict the new onset EGPA in these patients with severe asthma.