Influencing Factors of Treatment Response to Rituximab in Refractory Membranous Nephropathy.

Objective: This study aims to identify influencing factors associated with the efficacy of rituximab in treating refractory membranous nephropathy (MN), characterized by persistent proteinuria and unresponsive to conventional immunosuppressive therapies. We sought to determine clinical and biochemical predictors for positive therapeutic outcomes and optimize patient selection criteria.

Methods: A total of 160 patients with biopsy-confirmed refractory MN (meeting criteria of eGFR > 30 mL/min/1.73 m², significant proteinuria, positive PLA2R-Ab, and prior treatment failure) were studied. Patients received rituximab (375 mg/m²) with 24-month monitoring. Baseline demographic, clinical, and biochemical data underwent univariate and multivariate logistic regression analyses, while ROC curve analysis evaluated predictive accuracy.

Results: Responders (n=113) exhibited higher serum albumin, lower serum creatinine, reduced 24-hour urine protein, higher eGFR, and lower PLA2R-Ab levels (all P < 0.001) versus non-responders (n=47). Multivariate analysis identified these as independent predictors. The combined indices yielded an AUC of 0.99 (with 93.8% sensitivity and 97.9% specificity; P < 0.001), demonstrating excellent accuracy for identifying patients most likely to benefit from rituximab therapy.

Conclusion: Rituximab demonstrates efficacy in treating refractory MN, with specific clinical and biochemical markers providing significant predictors of treatment success. The biomarker combination (serum albumin, creatinine, 24-hour urine protein, eGFR, PLA2R-Ab) offers exceptional predictive accuracy for treatment outcomes, providing clinicians with a practical tool to guide personalized treatment decisions and optimize resource allocation in refractory MN management.