[Comparison of efficacy and safety of immunosuppressive therapy and rituximab targeting therapy in idiopathic membranous nephropathy].

Objective To assess the efficacy and safety of three treatment modalities (rituximab targeted B-cell therapy, calcium-phosphate inhibitor in conjunction with low-dose corticosteroids, and full-dose corticosteroids combined with cyclophosphamide) for patients at intermediate or high risk of idiopathic membranous nephropathy (IMN) and to analyze the factors impacting the remission rates of IMN. Methods A retrospective cohort study was conducted to analyze patients diagnosed with IMN in our nephrology department via renal biopsy, identifying a total of 148 patients at intermediate or high risk. These patients were categorized into three treatment groups: a RTX group with 60 patients receiving rituximab, a CNI group with 42 patients receiving calcineurin inhibitors, and a CTX group with 46 patients received cyclophosphamide. Baseline measurements of 24-hour urine protein, serum albumin, blood creatinine, uric acid, estimated glomerular filtration rate (eGFR), and serum anti-phospholipase A2 receptor antibody levels were recorded at the onset of the follow-up. Subsequently, changes in 24-hour urine protein, eGFR, remission rates, and occurrence of adverse events among the three patient groups were compared at 6, 12, and 18 months post-treatment. Moreover, COX regression analysis was employed to ascertain factors influencing the remission rate of IMN. Results At the outset of the follow-up period, no significant difference existed in baseline characteristics such as gender, age, 24-hour urine protein quantification, serum albumin, serum creatinine, uric acid, eGFR, serum anti-PLA2R antibody levels, body mass index (BMI), and systolic blood pressure among the patients, indicating the comparability of three groups. After 6 months, there were no notable changes in 24-hour urine protein quantification and eGFR among the three groups; however, remission rates in the RTX and CTX groups were lower than those in the CNI group. By the 12-month mark, 24-hour urine protein quantification in the RTX group significantly decreased compared to the CTX group, with overall remission rates showing no significant differences among the three groups. By the 18-month milestone, 24-hour urine protein quantification in the RTX group remained notably lower than that in the CTX group, with significantly higher eGFR levels. Additionally, the CTX group exhibited lower 24-hour urine protein quantification compared to the CNI group, with both RTX and CTX groups displaying higher remission rates than the CNI group. Predominant adverse reactions in the RTX group included infusion reactions and infections, whereas the CNI group were associated with metabolic syndrome and elevated serum creatinine, and the CTX group primarily experienced hepatic dysfunction. Multifactorial COX regression analysis revealed an association between baseline anti-PLA2R antibodies and remission rates of IMN (HR=1.162, 95% CI 1.078-1.249). Conclusion RTX therapy for IMN exhibits a gradual onset of action, boasting a superior disease remission rate at 18 months in comparison to CNI. It demonstrates a similarity to CTX in this aspect and offers prolonged maintenance of remission. Conversely, CNI demonstrates a rapid onset of action but poses a risk of exacerbating renal impairment in patients. Notably, elevated levels of serum anti-PLA2R antibodies emerge as an independent risk factor influencing remission in IMN.