Renalys Pharma, Inc. announced the completion of patient enrollment in its registrational Phase III clinical trial evaluating sparsentan for the treatment of IgA nephropathy in Japanese patients. The study aims to support a submission for marketing approval to the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan.
The Phase III trial is a multicenter, open-label, single-arm study designed to assess the efficacy and safety of sparsentan in approximately 30 Japanese patients diagnosed with IgA nephropathy. Renalys Pharma anticipates topline results, focusing on the urine protein/creatinine ratio (UP/C) endpoint, in the second half of 2025.
BT Slingsby, MD, PhD, MPH, Chief Executive Officer and Executive Chairman of Renalys Pharma, Inc., expressed gratitude to the participating medical institutions for their efforts in enabling the completion of patient enrollment ahead of schedule. He stated, "Through our continued collaboration and efforts, we are seeking to deliver this innovative treatment of sparsentan to patients as quickly as possible."
Sparsentan's Regulatory and Clinical Background
Sparsentan, originally developed by Travere Therapeutics, is an endothelin and angiotensin II receptor antagonist. Renalys Pharma holds exclusive rights for its development and commercialization in Japan and several other Asian countries. In September 2024, Travere received full FDA approval for sparsentan (marketed as FILSPARI® in the U.S.) to slow kidney function decline in adults with primary IgA nephropathy at risk of disease progression. This approval was based on positive long-term confirmatory results from the PROTECT Study, which demonstrated a significant reduction in proteinuria and preservation of kidney function compared to irbesartan.
Orphan Drug Designation
In November 2024, sparsentan received Orphan Drug Designation from the Japanese Ministry of Health, Labour and Welfare (MHLW) for primary IgA nephropathy. This designation is granted to drugs intended for conditions affecting fewer than 50,000 people in Japan and with high unmet medical needs, potentially shortening the approval process.
IgA Nephropathy: An Unmet Need in Japan
IgA nephropathy is a leading cause of kidney failure, characterized by the deposition of abnormal IgA proteins in kidney tissue, leading to inflammation and impaired kidney function. Ryutaro Shimazaki, Chief Development Officer of Renalys Pharma, noted the significant unmet medical need in Japan, where no approved drugs are currently indicated for this disease.
Renalys Pharma's Commitment
Renalys Pharma is dedicated to developing innovative therapies for kidney disease in Japan and Asia, with a primary focus on delivering sparsentan to patients as quickly as possible. The company aims to address the growing problem of "drug loss" by catalyzing access to new treatments for kidney disease patients in the region.
