Use of Rituximab as an off-Label medication in Glomerular Diseases: Clinical Perspective
Objectives: We review rituximab (RTX) use and outcomes in immune-mediated glomerular diseases (GN) and compare it to established literature. Methods: Adult GN patients who received RTX between January 2014 and January 2018 in three public hospitals were reviewed. Membranous nephropathy (MN) and minimal change disease (MCD) were considered diseases with literature supporting RTX use. Lupus nephritis (LN), 1o focal segmental glomerulosclerosis (1o FSGS), IgA nephropathy (IgAN), IgG4 related disease, and C3GN had insufficient literature support for RTX use. Clinical Remission was assessed six months after receiving RTX. Results: A total of 61 cases analyzed. RTX was an add on therapy in 87%. Remission rate was 95% in MCD and MN vs. 56 % in off-label group (P=.002). LN patients had a mean initial eGFR of 69mL/min. All class III LN achieved remission, and 11 of 21 class IV achieved remission. Mean initial eGFR for 1o FSGS was 33mL/min and it did not improve, and only 2 of 5 had partial resolution of proteinuria. Proteinuria improved in 3 of 5 IgG4-related disease cases with eGFR stabilization but failed to improve in C3GN cases with eGFR deterioration. Vasculitis cases (6 ANCA-associated vasculitis and 2 IgA vasculitis) were analyzed separately. Remission achieved in only 2 ANCA vasculitis cases, and none in IgA vasculitis cases. Conclusion: Our data support RTX use in resistant MCD and MN. RTX showed success in LN and IgG4 related disease, but not FSGS or C3GN. The small vasculitis cases number does not allow drawing a conclusion on RTX effectiveness.