Obinutuzumab Induced Decreases of PLA2R Antibodies in Membranous Nephropathy: a Pilot Study

Objective: To assess the disappearance rate (half-life) of anti-PLA2R antibodies in high-risk primary membranous nephropathy (pMN) patients treated with obinutuzumab (OBI), and to evaluate immunological and clinical remission, adverse events, and quality of life. Design: Open-label, single-center, prospective pilot intervention study conducted at Radboud University Medical Center. Population: 20 adult patients with high-risk PMN, defined by proteinuria ≥3.5 g/24h despite 6 months of supportive treatment with ACE inhibitors or ARBs. Intervention: OBI 1000 mg on days 1 and 15, with two additional infusions after 6 months if anti-PLA2R antibody levels remain positive and proteinuria exceeds 2 g/24h. Follow-up: Patients were monitored at baseline, and at weeks 1, 2, 4, 8, 12, 24, 37, and 52.