Obinutuzumab Following Rituximab Intolerance or Treatment Failure in Glomerular Disease: A Single-Centre Irish Case Series

Obinutuzumab is a humanized type II anti-CD20 monoclonal antibody that induces more profound B-cell depletion than rituximab and has emerged as a promising therapeutic option in immune-mediated kidney disease. However, published experience in glomerular disease remains limited, particularly among patients with rituximab hypersensitivity or treatment failure. We describe 13 patients with glomerular diseases treated with obinutuzumab at a tertiary nephrology centre between 2020 and 2025, including membranous nephropathy (n=3), lupus nephritis (n=6), minimal change disease (n=2), and MPO-ANCA-associated vasculitis (n=2). Six patients had prior rituximab hypersensitivity, comprising four episodes of anaphylaxis, one episode of serum sickness, and one acute infusion reaction, and two had rituximab-refractory disease. Eleven of 13 patients achieved remission (85%), including 9 complete and 2 partial remissions. Remission was observed across all disease subtypes. Five of six lupus nephritis patients achieved remission, while all patients with minimal change disease and ANCA-associated vasculitis achieved remission. All PLA2R-positive membranous nephropathy patients achieved immunologic remission. One mild infusion reaction and one serious infection were observed. No severe infusion reactions occurred despite prior rituximab hypersensitivity. Obinutuzumab demonstrated favourable efficacy and tolerability across multiple glomerular diseases and may represent an effective alternative B-cell depleting therapy in patients with rituximab intolerance or treatment failure.