Pierce has been a member of the board of directors since January 2017. He currently serves as entrepreneur-in-residence at Third Rock Ventures. At Third Rock, he co-founded Ambys Medicines and serves as interim Chief Medical Officer.  Pierce previously served in several roles at Biogen, most recently as Chief Medical Officer leading the hematology, cell and gene therapies division. Prior to Biogen, he served in small, large, public and private biotech/biopharma firms, including Bayer, Inspiration, Avigen, Selective Genetics and Amgen in the areas of tissue regeneration and hematology. Pierce is the co-author of more than 150 scientific papers and received more than 15 patents. He served on the medical and scientific advisory council, the board of directors and was President of the board of the National Hemophilia Foundation. Pierce also served on the Blood Products Advisory Committee at the FDA and the Committee on Blood Safety and Availability at the U.S. Department of Health and Human Services. He currently serves on the boards of directors of the World Federation of Hemophilia as the Vice President Medical and Global Blood Therapeutics.  Pierce received an M.D. and a Ph.D. in Immunology, both from Case Western Reserve University in Cleveland, and completed his postgraduate training in pathology and hematology research at Washington University in St. Louis.