Use of Biologics to Treat Relapsing and/or Refractory Eosinophilic Granulomatosis with Polyangiitis: data from a European Collaborative Study.

Objective To describe the efficacy and safety of biologics use for eosinophilic granulomatosis with polyangiitis (EGPA). Methods We conducted a retrospective European collaborative study including EGPA patients who received biologics for refractory and/or relapsing disease. Results Among 147 patients included, 63 received rituximab (RTX), 51 mepolizumab (MEPO) and 33 omalizumab (OMA). At inclusion, median (IQR) BVAS in the RTX, OMA and MEPO recipients were 8.5 (5-13), 2 (1-4.5) and 2 (1-5). In the RTX group, median BVAS fell to 1 (0-4.5) at 6 and 0 (0-2) at 12 months. Remissions, partial responses, failure and stop for adverse event were noted in 49%, 24%, 24% and 3%. For glucocorticoid (GC)-dependent asthma, MEPO had a much better GC-sparing effect and overall response than OMA. Remissions, partial responses, failure and stop for adverse event were noted in 15%, 33%, 48% and 4% for OMA, and 78%, 10%, 8% and 4% for MEPO. Remission rates were 76% and 82% at 12 months with MEPO 100 mg and 300 mg, respectively. Conclusion These results suggest that rituximab could be effective in EGPA vasculitis relapses. Mepolizumab is highly effective with a good safety profile in GC-dependent asthma. Our data suggest that 100 mg monthly could be an acceptable first-line dose in selected instances of EGPA recognizing though that this has not been compared to the validated dose of 300 mg monthly.