Albireo Pharma (NASDAQ: ALBO) has appointed Patrick Horn to serve as chief medical officer. He will succeed Paresh Soni, who is stepping down from the Boston company but will continue to serve as a consultant. Horn was most recently senior vice president, medical and clinical development at Switzerland-based Orphan Technologies. Albireo develops drugs to treat rare liver diseases. The company has started Phase 3 studies testing A4250, an experimental treatment for progressive familial intrahepatic cholestasis, a rare inherited liver disorder that in many cases leads to liver failure within the first 10 years of life.