Efficacy of conventional immunosuppressants in relapsing or refractory eosinophilic granulomatosis with polyangiitis: evidence from a Canadian single-centre cohort.

OBJECTIVES: To describe the efficacy of conventional immunosuppressants in disease control of relapsing or refractory eosinophilic granulomatosis with polyangiitis (EGPA) compared to recently published mepolizumab and rituximab studies. METHODS: A retrospective analysis from the Toronto Vasculitis Clinic was conducted. Patients with relapsing or refractory EGPA with similar entry criteria as the main mepolizumab (MIRRA) or rituximab (case-series) studies, who were started on conventional immunosuppressants, were assessed for remission at 24- and 52-weeks. Remission was defined as a Birmingham Vasculitis Activity Score of 0 and a prednisone dose of