Optimized RTX strategy plus structured glucocorticoid tapering for primary membranous nephropathy: a multicenter...

Area of Science:

• Nephrology
• Immunology
• Pharmacology

Background:

• Standard rituximab (RTX) regimens for primary membranous nephropathy (PMN) can lead to subtherapeutic drug exposure within 2-3 months due to altered pharmacokinetics.
• This suboptimal exposure may contribute to delayed remission, incomplete immunologic control, and increased relapse rates in PMN patients.
• An optimized RTX strategy was investigated to improve clinical and immunologic outcomes in PMN.

Purpose of the Study:

• To evaluate if an exposure-optimized RTX strategy combined with structured glucocorticoid tapering improves clinical and immunologic outcomes in primary membranous nephropathy (PMN).
• To compare the efficacy and safety of an exposure-optimized RTX regimen against standard RTX monotherapy in PMN patients.

Main Methods:

• A multicenter retrospective study included 182 PMN patients with nephrotic syndrome.
• 75 patients were analyzed after 1:2 propensity score matching, comparing an exposure-optimized strategy (interval RTX dosing with TDM-guided redosing) to standard RTX (weekly dosing for 4 weeks).
• Primary endpoint was complete remission (CR); secondary endpoints included near-CR, complete immunologic remission, and relapse rates.

Main Results:

• The exposure-optimized RTX group maintained higher RTX concentrations and a greater proportion of patients achieved therapeutic levels at 6 months.
• At 12 months, the optimized strategy showed significantly higher complete remission (64.0% vs. 22.0%) and complete immunologic remission (80% vs. 42%) rates.
• The optimized regimen was associated with earlier time to CR, higher cumulative CR and near-CR, and a significantly lower relapse rate (0% vs. 18.4%) compared to standard RTX.

Conclusions:

• An exposure-optimized RTX strategy, incorporating interval dosing, structured glucocorticoid tapering, and TDM-guided redosing, significantly improves remission rates and reduces relapse in PMN.
• This optimized approach leads to earlier and deeper immunologic response compared to standard RTX monotherapy.
• The findings support the use of exposure-optimized RTX for enhanced management of primary membranous nephropathy.