Viatris has announced positive top-line results from a phase 3 clinical trial evaluating the efficacy and safety of VR-205 (targeted-release budesonide formulation) (Nefecon) in Japanese adult patients with primary immunoglobulin A nephropathy (IgAN) at risk of developing end-stage renal disease.

The phase 3 clinical trial was a multicenter, interventional, open-label study designed to evaluate the efficacy and safety of 16 mg of VR-205 in Japanese adult patients with primary IgAN. Patients were treated for 9 months, followed by a 3-month follow-up period.

The study achieved its primary endpoint, with VR-205 demonstrating a 33.75 percent reduction in geometric mean Urine Protein-to-Creatinine Ratio (UPCR) at 9 months compared to baseline [95 percent CI: -45.27 to -19.80; p < 0.001]. These results were statistically significant and clinically meaningful, and were consistent with those observed in the global phase 3 program for the product.

In addition to a statistically significant and clinically meaningful reduction in UPCR at 6 and 12 months, VR-205 demonstrated a significant improvement in estimated Glomerular Filtration Rate (eGFR) and reductions in serum creatinine and Urine Albumin-to-Creatinine Ratio (UACR) at 9 months compared to baseline.

The overall therapeutic benefit of VR-205 was further supported by improvements in microhematuria and a sustained proteinuria reduction.

No study participants progressed to dialysis, kidney transplant or severe renal impairment (eGFR ≤15 mL/min per 1.73 m2) by the end of the study.

VR-205 was generally well tolerated over the 9-month treatment period, with a safety profile consistent with the known safety profile of targeted-release budesonide in non-Japanese patients.

Philippe Martin, Chief R&D Officer, Viatris, said, "We are pleased with these top-line results, which highlight VR-205 as a potentially meaningful, disease-modifying treatment option for patients with primary IgAN. In Japan, where IgAN incidence is the highest globally, VR-205 could become the first IgAN-specific, targeted-release budesonide oral therapy. This progress reflects the continued execution of Viatris' strategy focused on building a differentiated and increasingly innovative portfolio in Japan, with an emphasis on delivering therapies that provide meaningful value and address significant unmet needs."

Viatris is targeting submission of an NDA in Japan by the end of 2026.

Yuko Asami, Head of R&D, Viatris Japan, said, "Primary IgAN is a designated intractable disease in Japan, and remains a significant unmet need, with no curative treatment despite the risk of progression to end-stage renal disease. These top-line results mark an important step toward expanding treatment options for patients and healthcare providers."

In 2022, Calliditas Therapeutics AB and Viatris Pharmaceuticals Japan Inc., entered into an exclusive license agreement to obtain Marketing Authorisation (MA) and to commercialise VR-205 for the treatment of primary IgAN in Japan. It is currently a specialty drug approved and marketed as Tarpeyo in the US and as Kinpeygo in Europe.