Rituximab, Use and B Cell Depletion in Patients with Membranous Nephropathy- A Retrospective, Observational Study

Area of Science:

• Nephrology
• Immunology
• Pharmacology

Background:

• Idiopathic membranous nephropathy (MN) is a leading cause of nephrotic syndrome in adults.
• Rituximab (Rtx), an anti-CD20 monoclonal antibody, depletes B-cells and is an emerging therapy for MN.
• Evaluating Rtx efficacy in MN concerning B-cell depletion is crucial for optimizing treatment.

Purpose of the Study:

• To assess the efficacy and tolerability of Rituximab in patients with idiopathic membranous nephropathy (MN).
• To investigate the relationship between B-cell depletion and clinical remission in MN patients treated with Rtx.

Main Methods:

• Retrospective observational study of 20 patients with biopsy-proven primary MN.
• Patients received a fixed dose of 500mg IV Rituximab one month apart.
• Minimum follow-up of 12 months, assessing complete (CR) or partial remission (PR) and B-cell counts at 6 and 12 months.

Main Results:

• A composite remission rate of 66.7% (5.6% CR, 61.1% PR) was observed at 12 months.
• Mean PLA2R-Ab levels were significantly lower in patients achieving remission (17.8 RU/mL vs 311.7 RU/mL, P=0.01).
• Sustained B-cell depletion was observed in 84.3% at 6 months and 32% at 12 months, with no significant association with remission.

Conclusions:

• Rituximab demonstrates acceptable remission rates in both treatment-naïve and treatment-resistant idiopathic membranous nephropathy.
• No significant association was found between B-cell depletion levels and the achievement of remission in this cohort.