The Children's Hospital of Philadelphia's Stephen Grupp, MD, PhD, recently achieved a complete response in one of his patients by using an innovative treatment approach that involved reprogramming the child's own immune cells to attack an aggressive form of childhood leukemia, called acute lymphoblastic leukemia (ALL). Physicians can cure roughly 85 percent of ALL cases, but the remaining 15 percent of such cases resist standard therapy.

The prospects for 7-year-old Emma were grim when her cancer relapsed after she received the conventional treatment for ALL, the most common form of childhood leukemia and the most common childhood cancer. Faced with few viable treatment options, Dr. Grupp, director of Translational Research at the Center for Childhood Cancer Research, tried an experimental therapy using bioengineered T cells that were designed to multiply rapidly and destroy leukemia cells. Three weeks after the treatment, Emma's doctors found no evidence of cancer.

The research by Dr. Grupp builds upon his ongoing collaboration with Penn scientists who originally developed the modified T cells as a treatment for B-cell leukemias. The Penn team, led by Carl H. June, MD,, reported on early results of a trial using this cell therapy in adult chronic lymphocytic leukemia patients in August 2011. Dr. Grupp and his colleagues at Penn then adapted the treatment for use in treatment-resistant ALL cases.

The therapy represents a new approach in cancer treatment. As the workhorses of the immune system, T cells recognize and attack invading disease cells. However, cancer cells fly under the radar of immune surveillance, evading detection by T cells. CAR T cells (chimeric antigen receptor T cells) are engineered to specifically target B cells, which become cancerous in certain leukemias like ALL and CLL, as well as types of lymphoma, another cancer of the immune cells.

For more information about the groundbreaking being done at the Center for Childhood Cancer Research, please visit the CCCR website,. And to watch a short film about Drs. Grupp and June's work, visit the CHOP Research Blog.