He received his medical degree from Columbia University, completing a residency in internal medicine at Presbyterian Hospital in New York, and a fellowship in gastroenterology at Brigham and Women's Hospital in Boston. Following his residency and fellowship, Dr. Griffin joined the medical faculty of Columbia College of Physicians and Surgeons, where he held a number of academic, clinical research, teaching and management positions, as well as a solo private practice in New York. He subsequently moved to the biopharmaceutical industry, where he held positions of increasing responsibility, first at Forest Laboratories, and subsequently at Sanofi-Aventis, culminating with his appointment as Associate Vice-President, Clinical Development.