Efficacy and safety of mepolizumab in eosinophilic granulomatosis with polyangiitis: Insights from real-life cases and literature analysis

Background and aim: Recently, the MIRRA trial demonstrated the efficacy and safety of mepolizumab in refractory or relapsing eosinophilic granulomatosis with polyangiitis (EGPA) and the usefulness of this drug as a steroid-sparing agent. However, until now, only a few evidence is available about its effectiveness and safety in clinical practice. In this paper, we report our experience in the treatment of EGPA patients with mepolizumab in a real-world setting and review the current literature on this topic. Methods: We retrospectively enrolled 14 patients that underwent mepolizumab therapy for EGPA at any dose and with a follow-up of at least 3 months. For each patient, demographic and clinical manifestations of the disease, laboratory parameters, BVAS, asthma exacerbations, and therapeutic management were recorded at the beginning and at the end of mepolizumab therapy. Results: After a median follow-up of 16 months (3-60), all EGPA patients were in remission for both vasculitis and asthma manifestations. Mepolizumab was associated with a reduction in corticosteroids daily dose, with a significant number of patients able to discontinue corticosteroids (8/14 patients). No patients withdrew mepolizumab and no severe adverse events were recorded.  Conclusion: Our data support the long-term effectiveness of mepolizumab and, in particular, they are suggestive for a good safety profile of this drug among patients with EGPA. In the nearest future, the possibility to obtain a sustained remission in EGPA without the use of steroids should be investigated in larger controlled studies.