CHOP Opens Clinical Trial for Pediatric Leukemia

Published on in CHOP News

October 17, 2011 The Children’s Hospital of Philadelphia is now enrolling pediatric cancer patients in an innovative clinical trial that programs the immune system to attack blood cancers. In this study, called the CART19 trial, researchers will modify a child’s own T cells to attack specific types of cancer in their B cells.

The new Phase 1 pediatric trial has just begun to enroll a very small number of children with B cell cancers — B cell acute lymphoblastic leukemia (ALL) and B cell lymphoma — that resist standard treatment.

“After impressive progress against childhood leukemia beginning more than 30 years ago, cure rates have recently reached a plateau,” said pediatric oncologist Stephan A. Grupp, MD, PhD, the principal investigator of the CART19 trial at Children’s Hospital. “By harnessing a child’s own immune cells to attack the cancer, this immunotherapy approach has the potential to become a real step forward in advancing treatments for pediatric leukemia.”

In animal studies, a single dose of the modified T cells cleared leukemia rapidly, within 24-72 hours. Applying this to experimental human gene therapy, the researchers genetically engineer T cells to express a protein called chimeric antibody receptor (CAR), to attack another protein called CD19 on the surface of tumor cells. In a pilot study of adults with the B cell cancer chronic leukocytic leukemia, reported this August in Science Translational Medicine, these engineered T cells, called CART19 cells, multiplied 1,000-fold in patients’ bodies, and killed large numbers of tumor cells. Two of this study’s 3 adult patients have had complete remission persisting more than a year after treatment.

An expert in new treatments for B cell leukemias, Grupp was a co-author of the pilot study described above. That research, led by Carl June, MD, of the Perelman School of Medicine at the University of Pennsylvania, received broad news coverage as a potential new experimental therapy in leukemia.

As a Phase 1 trial, the current CART19 study is focused primarily on determining safety. If this approach proves safe, later trials will test the effectiveness of this treatment. Safety trials enroll a very small quantity of patients, so the number of participants will be highly limited. Candidates for this trial are children with relapsed or chemotherapy-resistant B cell ALL or B cell lymphoma. To be eligible, patients must also have a sufficient number of circulating T cells.

About The Children’s Hospital of Philadelphia

The Children’s Hospital of Philadelphia was founded in 1855 as the nation’s first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children’s Hospital has fostered many discoveries that have benefited children worldwide.

Its pediatric research program is among the largest in the country, ranking third in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 516-bed hospital recognition as a leading advocate for children and adolescents.