Chugai Files New Drug Application in Japan for Sparsentan for the Treatment of IgA Nephropathy

TOKYO - Chugai Pharmaceutical Co., Ltd. (TOKYO: 4519) announced that it filed a regulatory application with the Ministry of Health, Labour and Welfare for sparsentan for the treatment of patients with IgA nephropathy.

'In IgA nephropathy, a designated intractable disease, there are patients in whom proteinuria is not adequately controlled with existing treatments, and long-term decline in kidney function has remained an unmet challenge. Sparsentan has a novel mechanism of action that inhibits both the endothelin receptor and angiotensin II receptor, and has demonstrated a significant reduction in proteinuria in clinical studies, with results suggesting a potential benefit in preserving kidney function. Together with the convenience of once-daily dosing, we aim to support long-term disease management for patients and contribute to establishing a treatment foundation for IgA nephropathy,' said Dr. Osamu Okuda, President and CEO of Chugai.

This application is based on the results from the global Phase III study (the PROTECT study) conducted outside of Japan and Japanese Phase III study (the RE-021-001 study), both conducted in patients with IgA nephropathy with persistent presence of proteinuria.

In the global Phase III study (PROTECT study), sparsentan demonstrated a statistically significant improvement in the primary endpoint-the percent change from baseline in urine protein/creatinine ratio (UPCR) at Week 36-compared with the active control irbesartan (--49.8% vs --15.1%, p

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