Wells A. Messersmith

Wells A. Messersmith, MD, FACP is Division Chief of Medical Oncology and Associate Director for Clinical Research at the University of Colorado Cancer Center, where he also serves as Professor of Medicine. A nationally recognized expert in gastrointestinal oncology, Dr. Messersmith has led or participated in landmark phase I and phase II clinical trials across multiple GI tumor types, with substantial focus on pancreatic cancer and the development of agents targeting the KRAS-RAF-MEK-ERK signaling cascade. He has been a principal investigator for pivotal trials evaluating MEK inhibitors — including trametinib, cobimetinib, and binimetinib — in KRAS-mutated solid tumors including PDAC and colorectal cancer. His work has contributed significantly to characterizing the limitations of single-agent MEK inhibition in KRAS-driven cancers due to adaptive feedback resistance, and to identifying rational combination partners (EGFR inhibitors, SHP2 inhibitors, KRAS inhibitors) to overcome this resistance. Dr. Messersmith co-chaired the NCI-sponsored NCCTG/Alliance gastrointestinal tumor committee and has served in leadership roles for multiple cooperative group clinical trials in pancreatic and colorectal cancer. He has also conducted important translational work correlating molecular markers (KRAS mutation status, MAPK pathway activation scores) with response and resistance to MEK-targeted therapy, contributing to the biomarker-driven development of RAS pathway inhibitors. Dr. Messersmith has authored more than 150 peer-reviewed publications and is a highly regarded mentor to GI oncology fellows and junior faculty.