Seth Toback, MD, MMM, is Chief Medical Officer of ARMR Sciences, which is developing ARMR-100, a vaccine designed to protect against fentanyl overdose. A board-certified physician-scientist, he has more than 20 years of experience leading clinical development and medical affairs across biotech, pharmaceuticals, vaccines, infectious diseases and respiratory medicine. Before joining ARMR, he was Senior Vice President of Medical Affairs at Novavax from 2020 to 2026, and before that Vice President of Global Medical Affairs at bioMérieux. He earned his MD from Tufts University School of Medicine and his undergraduate degree from McGill University.