Study of Belimumab Combined With Rituximab Versus Rituximab Alone for Treating Primary Membranous Nephropathy in Adults Aged 18 to 75

What this Trial Is About

This research aims to evaluate the effectiveness of combining belimumab and intravenous rituximab compared to rituximab alone in adults with primary membranous nephropathy MN, a common cause of nephrotic syndrome characterized by an autoimmune attack on the kidneys. The study focuses on whether this combination can induce complete or partial remission, potentially improving treatment outcomes while minimizing side effects. MN affects adults of all ages and races, typically peaking in the fifth decade of life. The study has two parts Part A is an open-label phase assessing the pharmacokinetics of belimumab in participants with different proteinuria levels, all receiving weekly subcutaneous belimumab and rituximab infusions at weeks 4 and 6. Part B is a randomized, double-blind, placebo-controlled phase where participants receive either belimumab plus rituximab or placebo plus rituximab, with belimumab dosed weekly 400 mg initially, then 200 mg weekly for 52 weeks. Rituximab is given intravenously at weeks 4 and 6, with a possible second course at weeks 34 and 36 for those showing inadequate response at week 30. Participants are involved for up to 156 weeks, including a 52-week treatment period followed by a no-medication follow-up to week 156. Assessments include measuring remission status, proteinuria, anti-PLA2R levels, serum albumin, and quality of life at multiple timepoints. Safety is monitored throughout, tracking adverse events and immune responses. The primary outcome is remission at week 104, reflecting the delayed response typical in MN treatment.

Belimumab With Rituximab for Primary Membranous Nephropathy