Stephen Mitchener has been appointed senior vice president and chief business officer of Cambridge, MA-based Axcella Health. Mitchener’s experience includes 15 years at Novartis (NYSE: [[ticker:NVS]]), where he was most recently head of U.S. oncology strategy, partnering, and operations. In 2016, Axcella rebranded and turned its efforts toward developing drugs that treat metabolic dysregulation after it had initially focused on nutrition under the name “Pronutria.” Axcella’s pipeline now includes experimental treatments for diseases of the liver, muscle, and central nervous system.