Bruce Given, chief operating officer and head of R&D for Arrowhead Pharmaceuticals (NASDAQ: ARWR), has retired. Given’s responsibilities are being divided among the company’s chief medical officer, chief scientific officer, and chief commercial officer. Given, who joined Arrowhead in 2011, will serve as an advisor to the Pasadena, CA, company for at least one year. Arrowhead develops RNA interference therapies intended to stop genes from producing disease-causing proteins. The company’s most advanced wholly owned program, ARO-AAT, is in Phase 2 testing for alpha-1 antitrypsin deficiency, a rare liver disorder.