Mirum’s Phase 2b Volixibat Cuts Itch by 2.72 Points; Brelovitug Yields 100% HDV Response

Mirum’s Phase 2b VISTAS trial in PSC patients showed a mean 2.72-point reduction in cholestatic pruritus with a 1.64-point placebo-adjusted improvement (p<0.0001) and 56% of patients achieving ≥2-point itch reduction versus 26% on placebo. Mean serum bile acid levels fell by 33.7 µmol/L compared to a 2.1 µmol/L rise in placebo (p=0.0324), with trends toward better sleep and fatigue scores. Safety events were consistent with IBAT inhibition. A pre-NDA meeting is scheduled for summer 2026 ahead of a planned submission later in the year.

In the Phase 2b AZURE-1 trial in HDV patients (53% with cirrhosis), brelovitug achieved virologic response (≥2 log10 RNA reduction or undetectable HDV RNA) in 100% of patients on 300 mg weekly and 75% on 900 mg every four weeks at Week 24, with ALT normalization in 45% and 40% versus 0% in delayed treatment. Transient elastography showed liver stiffness declines of 3.6 kPa and 2 kPa respectively, versus a 1.1 kPa increase in controls. Mild injection-site reactions were most common. Topline data from Phase 3 AZURE-1 and AZURE-4 are expected in H2 2026, with potential BLA filing and U.S. launch in 2027.

A long-term analysis compared 41 PFIC patients treated with LIVMARLI for up to 4.8 years against 256 real-world controls, showing a 71% reduction in overall event-free survival events (HR=0.29; 95% CI 0.16-0.54; p=0.0001). The hazard for surgical biliary diversion fell by 95% (HR=0.05; p=0.0036) and for transplantation or death by 56% (HR=0.44; p=0.02), reinforcing maralixibat’s benefit in PFIC management.