Rituximab for induction and maintenance therapy of granulomatosis with polyangiitis: a single-centre cohort study on 114 patients.

OBJECTIVES: To assess efficacy and safety of rituximab (RTX) induction and maintenance therapy for granulomatosis with polyangiitis (GPA) in a single-centre cohort study.

METHODS: All patients with active GPA, not enrolled in trials, who received ⩾1 RTX infusion(s) for induction were included. At remission, protocolized maintenance RTX infusions were given every 6 months for 18 months. Kaplan-Meier curves were used to estimate survival rates. Univariable analyses identified factors associated with remission failure and relapse, and Cox models retained independent predictors of relapse.

RESULTS: One hundred and fourteen adults with relapsing (65%), refractory/grumbling (22%) or new-onset (13%) GPA received RTX for induction; 100 were given ⩾1 RTX maintenance infusion(s) and 90 received 500 mg every 6 months. Median daily prednisone induction dose was 30 mg; 76% of patients were still receiving a median daily prednisone dose of 5 mg at 2 years. Median follow-up was 3.6 years. Respective 2-year relapse-free survival and RTX retention rates were 85 and 78%. Serious infection and serious adverse event rates were 4.9 and 8.1 per 100 patient-years, respectively. Refractory/grumbling vs new-onset and/or relapsing GPA (P < 0.01 for each individually; P < 0.001 vs the latter two taken together), pachymeningitis (P < 0.05), pure granulomatous disease (P < 0.05) or estimated glomerular filtration rate ⩾60 ml/min (P < 0.01) were associated with remission failure. Multivariate analyses retained refractory/grumbling GPA (P = 0.05), subglottic stenosis (P < 0.005), ENT involvement (P = 0.01) and skin involvement (P < 0.0005) as independent predictors of relapse.

CONCLUSION: RTX induction and low-dose preemptive maintenance can effectively and safely induce sustained remission in GPA in a real-life setting.