Benralizumab for eosinophilic granulomatosis with polyangiitis: a retrospective, multicentre, cohort study

Background: Interleukin-5 (IL-5) inhibitors represent novel therapies for eosinophilic granulomatosis with polyangiitis (EGPA). This study assessed the effectiveness and safety of the IL-5 receptor inhibitor benralizumab in a European cohort of patients with EGPA. Methods This retrospective cohort study included patients with EGPA from 28 European referral centres of the European EGPA Study Group across six countries (Italy, France, UK, Russia, Spain, and Switzerland) who received benralizumab as any line of treatment between Jan 1, 2019, and Sep 30, 2022. We assessed the rates of complete response, defined as no disease activity (Birmingham Vasculitis Activity Score [BVAS] of 0) and a prednisone dose of up to 4 mg/day, in contrast to partial response, defined as a BVAS of 0 and a prednisone dose greater than 4 mg/day. Active disease manifestations, pulmonary function, variation in glucocorticoid dose, and safety outcomes were also assessed over a 12-month follow-up. Findings 121 patients with relapsing-refractory EGPA treated with benralizumab at the dose approved for eosinophilic asthma were included (64 [53%] women and 57 [47%] men; median age at the time of beginning benralizumab treatment 541 years [IQR 442-622]). Complete response was reported in 15 (124%, 95% CI 71-196) of 121 patients at month 3, 25 (287%, 195-394) of 87 patients at month 6, and 32 (464%, 343-588) of 69 patients at month 12; partial response was observed in an additional 43 (355%, 270-448) patients at month 3, 23 (264%, 176-370) at month 6, and 13 (188%, 104-301) at month 12. BVAS dropped from 30 (IQR 20-80) at baseline to 00 (00-20) at months 3 and 6, and to 00 (00-10) at month 12. The proportion of patients with systemic manifestations, active peripheral neurological disease, ear, nose, and throat involvement, and pulmonary involvement decreased, with an improvement in lung function tests. Six patients relapsed after having a complete response. The oral prednisone (or equivalent) dose decreased from 100 mg/day (50-125) at baseline to 50 mg/day (36-85) at month 3 (p<001) , to 50 mg/day (25-63) at month 6, and to 25 mg/day (00-50) at month 12 (p<00001). 19 (16%) of 121 patients had adverse events and 16 (13%) discontinued benralizumab. Interpretation These data suggest that benralizumab could be an effective treatment for EGPA in real-life clinical practice. Further clinical trials are required to confirm the efficacy of benralizumab in patients with a higher baseline disease activity.