Rituximab Plus Cyclosporine in Idiopathic Membranous Nephropathy

Description

This is a pilot intervention study to evaluate preliminary evidence of the safety and effectiveness of a novel combination immunosuppressive regimen, Rituximab plus cyclosporine, in the treatment of idiopathic membranous nephropathy. Membranous nephropathy is a condition that affects the kidney and involves damage to the walls of tiny blood vessels filters in the kidneys called glomeruli. This damage allows blood proteins to leak into the urine (proteinuria). As a result, patients have low protein levels in the blood, high blood cholesterol levels and often develop leg swelling. This combination of symptoms and signs is called the nephrotic syndrome. Some patients with membranous nephropathy develop impaired kidney function and a proportion of these patients may develop kidney failure. The immunosuppressive drugs that are most often used to treat membranous nephropathy include cyclophosphamide plus steroids or cyclosporine. These vary in their effectiveness among patients and there are side effects with each treatment. Rituximab alone has been used experimentally to treat membranous nephropathy in small clinical trials. It has been associated with decreased proteinuria of variable degrees in some patients. The purpose of this pilot study is to evaluate whether the combination of Rituximab plus cyclosporine, two drugs with different effects on the immune system, results in a greater number of remissions of the nephrotic syndrome and more sustained remissions than is expected with cyclosporine alone. Although each of these medications has been used separately in membranous nephropathy, the potential benefits and risks of this combination have not yet been formally explored. Patients age 18 years and older with idiopathic membranous nephropathy will be eligible to participate in this study. Pregnant and nursing women may not participate. Candidates must have persistent nephrotic syndrome despite a 6 month observation period and treatment with angiotensin converting enzyme inhibitors or angiotensin receptor blocker. Candidates will be screened with a medical history, physical examination, blood and urine tests, review of the medical records and kidney biopsy results. Participants will come to NIH in Bethesda, Maryland for evaluation and to receive intravenous infusions of Rituximab. Two doses of Rituximab will be given (2 weeks apart). Participants will also take cyclosporine pills twice a day. After 6 months, the dose of cyclosporine will be tapered over several weeks and then discontinued. Patients will be re-treated with a second course of Rituximab (two infusions given two weeks apart) after a minimum of 6 months has passed since completing the first course of Rituximab. The exact timing of the second course of Rituximab will depend on the results of blood tests. All patients will be followed for a minimum of 24 months from the time that therapy is initiated.

Details