Evaluation of mepolizumab (MPZ) treatment in Eosinophilic Granulomatosis with Polyangiitis (EGPA) patients in an asthma clinic

<bold>INTRODUCTION:</bold> EGPA is a rare and systemic disease. Treatment mainly relies on oral corticosteroids (OCS). Therefore, immunosuppressive (IS) treatments are often prescribed as OCS-spare agents and to prevent relapses. Recently, MPZ proved to be an efficacious treatment for EGPA. Pulmonologists usually treat patients in eosinophilic phase of EGPA, before systemic vasculitis damage is evident. The aim of our study was to evaluate activity disease in our patients with EGPA treated with MPZ. <bold>METHODS:</bold> We performed a retrospective study of 13 adult EGPA patients treated with MPZ followed for at least 1 year in our asthma clinic. Functional-clinical variables and Birmingham Vasculitis disease Activity Score (BVAS) data were collected, 1 year before and after MPZ. Also, the results were evaluated according to different doses of MPZ (100 - 300mg). <bold>RESULTS:</bold> In our study, 69% were men with a mean age of 60±15,3 years. The BVAS score was: 9.1±5.7 at diagnosis, 5.7±5.2 at the beginning of MPZ and 1.4±1.5 after MPZ. After 12 months of MPZ, blood eosinophil percentage (6.9 vs. 1%), OCS (92,3% vs. 38,5%) and IS treatment (38.5% vs. 0%)(p<0,05) were reduced. All our patients improved their symptoms (p<0.001) and asthma control (ACT 20.5 vs 22.1)(p=0,695). No relapses were detected. A significant BVAS improvement score was observed (6.4 preMPZ vs 1.4 postMPZ 100mg y 6 preMPZ vs 1.3 postMPZ 300mg)(p<0,05) regardless of MPZ dose. <bold>CONCLUSIONS:</bold> Our patients with EGPA and MPZ showed clinical improvement, significant reduction in BVAS score, blood eosinophils and IS-OCS treatment, in the absence of relapses. Both doses of MPZ 100-300mg achieved clinical improvement in our series.