Johnathan Maher

Johnathan Maher, PhD, currently serves as the Vice President and Head of Medical Affairs at Day One Biopharmaceuticals since January 2025. Previously, Maher held the same title at Ambrx from September 2023 to January 2025 and served as Executive Director of Medical Affairs at Arcus Biosciences from November 2020 to September 2023. Maher has extensive experience in medical affairs, having contributed to notable roles at Amgen as Asset Lead Medical Director for the AML Portfolio and AbbVie as Senior Scientific Director of Oncology Global Medical Affairs. Maher's career also includes a significant position at Dendreon, where responsibilities encompassed leading Medical Affairs Strategy and overseeing clinical and regulatory documentation. Maher earned a PhD in Molecular Cell and Developmental Biology from the University of Miami Miller School of Medicine and a BS in Food Science from Virginia Tech.