ZUMA-3 is a Phase I clinical trial exploring the use of the CAR T-cell product axicabtagene ciloleucel in relapsed/refractory acute lymphoblastic leukemia (NCT02614066). In this interview, William Wierda, MD, PhD, of the University of Texas MD Anderson Cancer Center, Houston, TX, discusses the results presented at the American Society of Hematology (ASH) 2018 Annual Meeting and Exposition in San Diego, CA, which focused on the safety and toxicity of this therapy, and identifying the optimal dose to be tested in a Phase II trial.