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Stephen M. Hahn

Chief Medical Officer, Preemptive Medicine and Health Security Initiative

Steve Hahn, M.D., is Chief Medical Officer of Flagship Pioneering’s Preemptive Medicine and Health Security Initiative. In this role, he is responsible for designing, pursuing, and advancing explorations and companies for this emerging initiative.

Steve brings two decades of distinguished leadership in healthcare strategy, oncology medical practice, and translational/clinical research to this role. He served as the 24th U.S. Food and Drug Administration (FDA) Commissioner from 2019 to 2021 overseeing both COVID and non-COVID regulatory affairs, including therapeutics and vaccine development, devices, diagnostics, and clinical trials.

Prior to his FDA appointment, Steve was the Chief Medical Executive at The University of Texas MD Anderson Cancer Center. He was named Deputy President and Chief Operating Officer in 2017 and was responsible for the day-to-day operations of the Cancer Center. Prior to MD Anderson, he served as an Assistant Professor at the University of Pennsylvania’s Perelman School of Medicine where he was appointed Chair of its Radiation Oncology Department in 2005.

Steve focused his translational research efforts on the evaluation of the tumor microenvironment, signal transduction pathways involved in tumor response to therapies and proton therapy. He has authored more than 220 peer-reviewed original research articles and has experience in medical product development.

Steve earned his M.D. from Temple University and received his B.A. in Biology from Rice University. He was an internal medicine resident at the University of California San Francisco before completing a fellowship and residency at the National Cancer Institute in Bethesda, Maryland.