Mirum Pharmaceuticals Slides as FDA Feedback Clouds Volixibat Timeline

Mirum Pharmaceuticals (MIRM) stock dropped 10.4% after the FDA recommended a Phase 3 study for its drug volixibat, delaying its potential NDA submission despite strong second-quarter sales and raised full-year guidance. The regulatory setback for volixibat, intended for cholestatic pruritus due to PSC, has raised investor concerns about the timeline and execution risk for this key pipeline program. Insiders have sold off shares, while institutional investors show mixed activity, with some significantly adding to their holdings.