Glucocorticoid-sparing effect of mepolizumab for severe eosinophilic granulomatosis with polyangiitis: a retrospective single-center observational study

Abstract

Abstract Background This study evaluated the glucocorticoid (GC)-sparing effect of mepolizumab (MEP) in severe eosinophilic granulomatous polyangiitis (EGPA). Methods Participants were patients diagnosed with EGPA according to Watts’ algorithm and who underwent outpatient care at Juntendo Hospital between November 2017 and January 2023. This longitudinal, observational study consisted of a retrospective analysis of medical records. Results Thirty-five patients were analyzed. The reasons for receiving MEP, by numbers of patients, were as follows: eosinophilia, 3; neuropathy exacerbation, 3; persistent neuropathy, 3; GC-sparing effect, 3; asthma exacerbation, 2; and skin ulcer exacerbation, 1. Compared with the MEP (−) group, the MEP (+) group had higher rates of remission and concomitant azathioprine treatment, and lower peripheral blood eosinophil count and GC dosage at last observation. The median GC dose after MEP was 2.8 (0.0–4.3) mg/day as prednisolone equivalent dose less than before. Conclusions The addition of MEP may be considered for patients with severe EGPA, with or without the use of azathioprine.