Efficacy and safety of obinutuzumab in refractory membranous nephropathy: a single-arm meta-analysis.

Membranous nephropathy (MN) constitutes an autoimmune glomerular disorder and represents the most frequent etiology of primary nephrotic syndrome in adults. Although obinutuzumab exhibits favorable efficacy in managing refractory MN, outcomes diverge across individual investigations. Consequently, the present meta-analysis is undertaken to systematically evaluate the clinical efficacy and safety of obinutuzumab in individuals with refractory MN. A systematic search was conducted across the Cochrane Library, Embase, Web of Science, and PubMed to determine relevant clinical investigations published up to November 12, 2025. Treatment effects were quantified employing the pooled proportion rate with 95% confidence interval (CI), mean difference (MD, 95% CI), and standardized mean difference (SMD, 95% CI). Heterogeneity was examined via the I² statistic. Subgroup analyses were implemented based on the geographic distribution of the study population and duration of follow-up. All extracted data were subjected to statistical analysis using R (v4.5.2). The present meta-analysis ultimately incorporated 12 articles (222 individuals) after applying the eligibility criteria. Concerning remission rates, the overall clinical remission rate reached 86% (95% CI: 80% to 90%), the complete clinical remission rate stood at 31% (25% to 37%), the partial clinical remission rate was 55% (49% to 63%), and the immunologic remission rate achieved 88% (81% to 92%). Obinutuzumab reduced proteinuria (SMD = -1.2, 95%CI -1.37 to -1.03) and raised serum albumin (MD = 12.5, 95%CI 9.91-15.08), while eGFR showed no significant change (MD = 3.23, 95%CI -3.76-10.21). The pooled adverse event rate was 29% (95%CI 15%-48%), with two fatal pneumonia-related events: severe COVID-19 pneumonia and pneumonia-induced respiratory failure. Obinutuzumab demonstrates marked efficacy in treating refractory MN, with an overall clinical remission rate of 86% and a low incidence of severe adverse events. This profile signifies a potential therapeutic role for this condition. However, all raw data included in this meta-analysis were derived from uncontrolled retrospective single-arm trials and case series. Given factors such as selection bias, the remission rate may be overestimated. Large-scale, multicenter randomized controlled trials are necessary for verification in future investigations. https://www.crd.york.ac.uk/PROSPERO/, identifier CRD420251231344.