"These new and expanded data provide significant proof that T cells engineered to express cancer-targeting chimeric antigen receptors not only work, but work dramatically and in a sustained manner in patients with relapsed, treatment-resistant leukemia, and further demonstrate the potential of this approach to help these patients achieve complete response," said study author Michael Kalos, PhD, of the University of Pennsylvania Perelman School of Medicine in Philadelphia. "Further, our results show that we can potentially measure and track the activity of these engineered cells in the body as a way to monitor treatment, an exciting finding considering that this treatment is often the last hope for these patients."Dr. Kalos will present this study during an oral presentation at 5:00 p.m. CST on Sunday, December 8, in Riverside Rooms R02-R03 of the Ernest N. Morial Convention Center. T Cells Engineered With a Chimeric Antigen Receptor (CAR) Targeting CD19 (CTL019) Produce Significant In Vivo Proliferation, Complete Responses and Long-Term Persistence Without GVHD in Children and Adults With Relapsed, Refractory ALL [ 67 ] This study report, which provides select results from a group of cell therapy trials conducted by investigators at the Children's Hospital of Philadelphia and the University of Pennsylvania, used the chimeric antigen receptor (CAR) cell engineering approach to manipulate the T cells of 22 children and five adults with relapsed, treatment-resistant acute lymphocytic leukemia. After treatment with their own cells re-engineered to seek, attack, and kill leukemic cells, 24 patients (19 children, five adults) achieved a complete response (CR). One patient has remained in remission for a year and had detectable engineered cells at 18 months post infusion, indicating that the cells show potential to persist in the body. Of those who achieved CR at one month, six (five children, one adult) have since relapsed. No patients experienced immediate infusion-related toxicities or graft-versus-host disease. The most significant toxicity each patient experienced was a complication known as delayed cytokine release syndrome, characterized by high fever, muscle pain, and nausea, which developed as a result of successful T cell expansion, driven by the interaction between engineered T cells and the patients' leukemic cells. "Our results serve as another important milestone in demonstrating the potential of this treatment for patients who truly have no other therapeutic options," said study author Stephan Grupp, MD, PhD, of the Children's Hospital of Philadelphia, Abramson Cancer Center and the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. "These data also demonstrate that these engineered hunter cells greatly expand and then persist in patients, allowing for long-term disease control. This allays previous concerns that infused cells only survive for a limited time. In the relatively short time that we've observed these patients, we have reason to believe that this treatment could become a viable therapy for their relapsed, treatment-resistant disease and we look forward to continuing to evaluate their long-term response." Dr. Grupp will present this study during an oral presentation at 5 p.m. CST on Sunday, December 8, in La Nouvelle Ballroom C of the Ernest N. Morial Convention Center. Effective Treatment of Chemotherapy-Refractory Diffuse Large B Cell Lymphoma With Autologous T Cells Genetically-Engineered to Express an Anti-CD19 Chimeric Antigen Receptor [ 168 ] This abstract reports on the treatment of 15 patients with anti-CD19 CAR-expressing T cells, all of whom had advanced B cell malignancies, and eight of whom had large B cell lymphomas. This is the first report of successful treatment in patients with chemotherapy-refractory primary mediastinal B cell lymphoma and diffuse large B cell lymphoma. In the trial, the 15 adult patients with varying types of lymphoma or leukemia received an infusion of their own genetically modified T cells following a chemotherapy conditioning regimen of cyclosphamide and fludarabine. Six patients achieved complete remission and six achieved partial remission. Acute toxicities such as fever, low blood pressure, focal neurologic deficits, and delirium resolved in less than three weeks.