Mepolizumab for Eosinophilic Granulomatosis With Polyangiitis: A European Multicenter Observational Study
Authors: Alessandra Bettiol, Maria Letizia Urban, Lorenzo Dagna, Vincent Cottin, Franco Franceschini, Stefano Del Giacco, Franco Schiavon, Thomas Neumann, Giuseppe Lopalco, Pavel Novikov, Chiara Baldini, Carlo Lombardi, Alvise Berti, Federico Alberici, Marco Folci, Simone Negrini, Renato Alberto Sinico, Luca Quartuccio, Claudio Lunardi, Paola Parronchi, Frank Moosig, Georgina Espígol‐Frigolé, Jan Schroeder, Anna Luise Kernder, Sara Monti, Ettore Silvagni, Claudia Crimi, Francesco Cinetto, Paolo Fraticelli, Dario Roccatello, Angelo Vacca, Aladdin J. Mohammad, Bernhard Hellmich, Maxime Samson, Elena Bargagli, Jan Willem Cohen Tervaert, Camillo Ribi, Davide Fiori, Federica Bello, Filippo Fagni, Luca Moroni, Giuseppe Alvise Ramirez, Mouhamad Nasser, Chiara Marvisi, Paola Toniati, Davide Firinu, Roberto Padoan, Allyson Egan, Benjamin Seeliger, Florenzo Iannone, Carlo Salvarani, David Jayne, Domenico Prisco, Augusto Vaglio, Giacomo Emmi
Journal: Arthritis & Rheumatology (2021)

Mepolizumab proved to be an efficacious treatment for eosinophilic granulomatosis with polyangiitis (EGPA) at a dose of 300 mg every 4 weeks in the randomized, controlled MIRRA trial. In a few recently reported studies, successful real-life experiences with the approved dose for treating severe eosinophilic asthma (100 mg every 4 weeks) were observed. We undertook this study to assess the effectiveness and safety of mepolizumab 100 mg every 4 weeks and 300 mg every 4 weeks in a large European EGPA cohort.We included all patients with EGPA treated with mepolizumab at the recruiting centers in 2015-2020. Treatment response was evaluated from 3 months to 24 months after initiation of mepolizumab. Complete response to treatment was defined as no disease activity (Birmingham Vasculitis Activity Score [BVAS] = 0) and a prednisolone or prednisone dose (or equivalent) of ≤4 mg/day. Respiratory outcomes included asthma and ear, nose, and throat (ENT) exacerbations.Two hundred three patients, of whom 191 received a stable dose of mepolizumab (158 received 100 mg every 4 weeks and 33 received 300 mg every 4 weeks) were included. Twenty-five patients (12.3%) had a complete response to treatment at 3 months. Complete response rates increased to 30.4% and 35.7% at 12 months and 24 months, respectively, and rates were comparable between mepolizumab 100 mg every 4 weeks and 300 mg every 4 weeks. Mepolizumab led to a significant reduction in BVAS score, prednisone dose, and eosinophil counts from 3 months to 24 months, with no significant differences observed between 100 mg every 4 weeks and 300 mg every 4 weeks. Eighty-two patients (40.4%) experienced asthma exacerbations (57 of 158 [36%] who received 100 mg every 4 weeks; 17 of 33 [52%] who received 300 mg every 4 weeks), and 31 patients (15.3%) experienced ENT exacerbations. Forty-four patients (21.7%) experienced adverse events (AEs), most of which were nonserious AEs (38 of 44).Mepolizumab at both 100 mg every 4 weeks and 300 mg every 4 weeks is effective for the treatment of EGPA. The 2 doses should be compared in the setting of a controlled trial.