What's Happening?
Mirum Pharmaceuticals has announced that its VISTAS Phase 2b study of volixibat, an investigational oral ileal bile acid transporter (IBAT) inhibitor, has met its primary endpoint in treating primary sclerosing
cholangitis (PSC). The study involved 158 patients and demonstrated a statistically significant reduction in cholestatic pruritus, a common and debilitating symptom of PSC. The primary analysis cohort showed a 2.72 point improvement in pruritus, with a placebo-adjusted difference of 1.64 points. These results suggest volixibat could become the first approved treatment for PSC, a rare liver disease affecting approximately 30,000 people in the U.S. The study's findings will be presented at the EASL International Liver Congress 2026.
Why It's Important?
The successful results of the VISTAS study are significant as they offer hope for a treatment in a field where no approved therapies currently exist. PSC is a progressive liver disease that can lead to severe complications, including liver failure and increased cancer risk. The potential approval of volixibat could provide a much-needed therapeutic option for patients suffering from the burdensome symptoms of PSC, such as severe itching and fatigue. This development could also pave the way for further research and treatment options in cholestatic liver diseases, potentially improving the quality of life for many patients.
What's Next?
Mirum Pharmaceuticals plans to hold a pre-New Drug Application (NDA) meeting with the U.S. Food and Drug Administration (FDA) in the summer of 2026, with an NDA submission expected in the second half of 2026. The company is also preparing to present the full results of the VISTAS study at the EASL International Liver Congress. Additionally, Mirum anticipates topline data from its VANTAGE Phase 2b study of volixibat in primary biliary cholangitis (PBC) in early 2027. These steps indicate a strategic move towards regulatory approval and potential market introduction of volixibat.
