Thornberry joined Merck Research Laboratories in Rahway, New Jersey as a biochemist in 1979. In 1999 she was appointed the Director of Enzymology, and in 2001 the Director of Metabolic Disorders, with further promotions in 2007, 2009 and 2011. At her retirement from Merck in 2013 Thornberry held the position of Senior Vice President and Franchise Head, Diabetes and Endocrinology. While an independent consultant to the biotechnology and pharmaceutical industries, Thornberry joined the boards of directors of Intarcia Therapeutics and Abide Therapeutics Both companies are involved in drug discovery targeting diabetes. As of November 1, 2015, Thornberry became CEO of Kallyope Inc. in New York City.
Research
Thornberry's research areas include obesity, diabetes, osteoporosis, fertility and contraception. Her work has led to the development of drug candidates including FDA-approved treatments for Type 2 diabetes. Thornberry was involved in early enzymology research on Lisinopril, an angiotensin converting enzyme inhibitor used for the treatment of hypertension. Thornberry also helped to identify Niemann-Pick C1-Like 1 as the target of ezetimibe, an inhibitor of cholesterol absorption. In 1992, her work on proteases led to the identification of the first caspase, caspase-1/Interleukin-1 converting enzyme. She determined that ICE was the cysteine protease responsible for IL-1β processing in monocytes. Thornberry also developed a novel method for analyzing protease specificities in combinatorial libraries of positional scanning substrates. Her work has led to the broader study of proteases in apoptosis. Beginning in 1999, Thornberry led the biological team for the development of Januvia™, a once-a-day oral medication that inhibits the dipeptidyl peptidase-4 enzyme and improves glucose tolerance to treat Type 2 diabetes. Ann E. Weber led the corresponding chemistry team for the project. The drug was approved by the FDA in October 2006. Janumet™, a drug combining sitagliptin and metformin was also approved, in April 2007. In 2007, the research team at Merck received the Prix Galien USA award for their work on Januvia™. The Januvia™ project was the first project at Merck to be co-lead solely by women, and the first project co-lead solely by women to win the Discoverers Award. At Kallyope Inc., drug discovery focuses on the study of the brain and the gut, examining connections between neuroscience and neural circuits and the gut and internal organs, to better understand and improve health and nutrition. Thornberry also serves on the Boards of Directors of Intarcia Therapeutics, which is developing diabetes medicine, and of Abide Therapeutics, which is exploring the serine hydrolase family as drug targets.
