Dr. O�Brien received his M.D. from Dartmouth Medical School in Hanover, New Hampshire. His training included an Internship and Residency in Internal Medicine at St. Vincent�s Medical Center in New York City and a Clinical Associate/Medical Staff Fellowship in Medical Oncology at the National Cancer Institute, NIH in Bethesda, Maryland. Further training included a Medical Oncology/Hematology Fellowship at Memorial Sloan-Kettering Cancer Center in New York City. His Post Doctoral Fellowship was in the Laboratory of Nucleic Acid Enzymology at Sloan-Kettering Institute for Cancer and as a Research Associate in the Laboratory of Molecular Pharmacology at Sloan-Kettering Institute where he investigated the mechanisms of drug resistance in clinical specimens from patients with hematologic malignancies and solid tumors. Dr. O�Brien was Assistant Professor of Medicine at Cornell University Medical College, Attending Physician at Memorial Sloan-Kettering Cancer Center in the Division of Hematologic Oncology and the Developmental Chemotherapy Service. Dr. O�Brien also served as the Executive Director, Oncology, Medical and Scientific Affairs for PharmaNet, Inc. in Princeton, New Jersey. Dr. O�Brien next served as Vice President, Clinical Research and Development for Aton Pharma, Tarrytown, NY, where he had overall responsibility for the design and execution of Global Clinical Development Programs. Prior to joining Sopherion Therapeutics, Dr. O�Brien�s most recent position was as Clinical Science Leader, Pharma Development, Medicine-Oncology for Hoffman-La Roche in Nutley, NJ where his responsibilities included design and execution of Global Clinical Development plans for drugs in the Roche Oncology portfolio, leading a global team of Physicians and Scientists in clinical development programs.