Stephan Grupp, MD, PhD, from the Children’s Hospital of Philadelphia, Philadelphia, PA, discusses the results of a global registration trial (NCT02435849) of the efficacy and safety of CTL019 in pediatric patients and young adults with relapsed/refractory acute lymphoblastic leukemia (ALL) at the American Society of Hematology (ASH) Congress 2016 in San Diego, CA. This is the first global trial for a cell therapy in this patient group. Dr Grupp explains that CAR-T-cells, which have been in development for a number of years, are engineered T-cells which can potentially attack cancer, and significant clinical results have been seen in a single-institution trial. In this trial, involving 25 centers in 11 countries, the safety and efficacy of CTL019 was assessed in high-risk relapsed and refractory pediatric and young adult ALL patients. Dr Grupp summarises the results of this study, which showed an initial complete response (CR) rate of 82%, and an overall survival (OS) at 6 months of 89%, with results very similar to the single institution trial. CTL019 was delivered with a high level of safety, and cytokine release syndrome (CRS) was well-managed due to extensive training programs for physicians, with no CRS-associated deaths in the trial. He concludes that from both an efficacy and safety standpoint, the global registration trial worked out well.