Mirum jumps after announcing interim results from two studies of volixibat

Shares of Mirum Pharmaceuticals are moving higher today after the company announced interim results from two Phase 2b studies evaluating volixibat, an oral ileal bile acid transporter inhibitor in patients with primary biliary cholangitis, or PBC, and primary sclerosing cholangitis, or PSC. Interim results from the VANTAGE study evaluating volixibat in patients with PBC demonstrated a statistically significant improvement in pruritus for volixibat and a placebo-adjusted difference of -2.32 points in the primary endpoint, as measured by the Adult ItchRO scale. 75% of patients on volixibat achieved a greater than 50% reduction in serum bile acids. In addition, there was a significant improvement in fatigue at week 16 with volixibat compared to placebo. No new safety signals were observed, and adverse events were similar between the 20 mg and 80 mg treatment groups. The most common adverse event was diarrhea with all cases mild to moderate, and mostly transient; one case resulted in discontinuation. Four patients experienced serious adverse events, including one in the placebo arm. There were no clinically meaningful changes in liver biomarkers. Based on these results, the VANTAGE PBC trial will continue with a volixibat dose of 20 mg twice daily. Concurrently, the interim analysis for the VISTAS PSC study was conducted and the independent data review committee recommended that the study continue with the selected volixibat dose of 20 mg twice daily, with no changes to the study. The criteria for continuation included safety as well as a predefined threshold for efficacy. The sponsor and investigators are blinded to the interim results and analysis. “The interim data from the VANTAGE study provide outstanding results in relation to what has been shown for treatment of pruritus in PBC,” said Joanne Quan, MD, chief medical officer at Mirum. “With both VISTAS and VANTAGE advancing to enroll their confirmatory portions, we are excited about volixibat as a potential future option to help patients overcome one of the most prevalent and burdensome symptoms of these rare liver diseases.” In Monday morning trading, shares of Mirum have advanced $3.55, or 14%, to $29.47.