International leader in clinical research in leukemia and prolific clinical investigator. Author and coauthor of nearly 1,000 journal articles. Developer of the second generation tyrosine kinase inhibitor bosutinib and the third generation ponatinib, which are widely used today, as well as, omacetaxine, a drug approved for patients with chronic myeloid leukemia where tyrosine kinase inhibitors have stopped working. Most recently, led the development of glasdegib, a smoothened inhibitor approved for the treatment of older patients who have acute myeloid leukemia as well as other conditions, like heart disease or moderate kidney disease, that preclude use of standard intensive induction chemotherapy. Current research emphasis includes development of new therapies for leukemia, developing predictive models, reducing the toxicity of cancer therapy, and improving quality of life of patients with leukemia.