Sparsentan Designated Orphan Drug for Primary IgA Nephropathy in Japan

Renalys Pharma, Inc., a biopharmaceutical company in its late clinical development stages, announced that its drug candidate, sparsentan, received Orphan Drug Designation from the Japanese Ministry of Health, Labour and Welfare for treating primary IgA nephropathy. This designation was granted on November 27, 2024, highlighting sparsentan's potential to address significant unmet medical needs within a patient population of fewer than 50,000 in Japan.

The Orphan Drug Designation is crucial because it prioritizes the review process, potentially accelerating the approval time for Marketing Authorization by several months. This expedited process is vital for conditions like IgA nephropathy, a leading cause of kidney failure. IgA nephropathy is characterized by deposits of abnormal IgA proteins in kidney tissues, leading to impaired kidney function and inflammation. Currently, there are no approved treatments for this disease in Japan, underscoring the high unmet medical need.

Ryutaro Shimazaki, Chief Development Officer of Renalys Pharma, emphasized the importance of this development. He noted that sparsentan, already approved in Europe and the United States, holds significant promise for Japanese patients. Renalys Pharma has secured the rights for sparsentan across several Asian countries and is leveraging global phase III PROTECT data to advance its development in Japan. The Orphan Drug Designation for sparsentan is seen as a pivotal step towards addressing the loss of kidney function in IgA nephropathy patients, with the company committed to bringing this innovative treatment to market as swiftly as possible.

Developed by Travere Therapeutics, sparsentan has been licensed exclusively to Renalys Pharma for development and commercialization in Japan and several other Asian countries. In September 2024, sparsentan received full FDA approval in the United States under the brand name FILSPARI®, aimed at slowing kidney function decline in adults with primary immunoglobulin A nephropathy at risk of disease progression.

Renalys Pharma's mission is to enhance the lives of patients in Japan and Asia by developing groundbreaking therapies for kidney diseases. The company's foremost goal is to expedite the availability of sparsentan to patients in need.

IgA nephropathy is a significant health concern in Japan, contributing substantially to chronic kidney disease (CKD) and end-stage renal disease (ESRD). The disease is recognized as one of the primary causes of kidney failure. It manifests when abnormal IgA proteins accumulate in kidney tissues, causing inflammation and impaired kidney function. Despite its prevalence and severity, there remains a considerable gap in effective treatments for IgA nephropathy in Japan, highlighting the critical need for new therapeutic options.

Renalys Pharma, established in April 2023 by Catalys Pacific and SR One, is a privately held biopharmaceutical company based in Tokyo. The company focuses on developing innovative treatments for renal diseases, targeting unmet medical needs in Japan and other Asian regions. Renalys Pharma's commitment extends to overcoming the challenges of "drug loss" by facilitating access to novel treatments for patients suffering from kidney diseases across Asia.