Mark Osterman, M.D., M.S.C.E.

Dr. Osterman is responsible for leading Xencor’s clinical development strategy and execution in autoimmune disease. Prior to joining Xencor in September 2025, he served in multiple clinical leadership positions at Bristol Myers Squibb. As Vice President, Early Differentiation and Pipeline for Immunology, Cardiovascular and Neuroscience, he provided cross-functional strategic leadership for all early pipeline assets in these therapeutic areas through Phase 2. In 2021, he joined BMS as Vice President and Disease Area Head of Gastroenterology within the Immunology R&D group. From 2005 to 2021, he was on the faculty at the University of Pennsylvania School of Medicine and completed his tenure as Associate Professor of Medicine and internationally regarded clinical researcher and key opinion leader in inflammatory bowel disease. Dr. Osterman received his M.D. from Harvard Medical School, M.S. in clinical epidemiology from the University of Pennsylvania, and B.A. from Harvard University. He completed gastroenterology fellowship at the University of Pennsylvania School of Medicine and internal medicine residency at Brigham and Women’s Hospital.