Cell Therapy Successfully Treats Cancer in Clinical Study

Rebecca Lewis February 27, 2014

The largest clinical study ever conducted to date of patients with advanced leukaemia found that 88 per cent achieved complete remissions after being treated with genetically modified versions of their own immune cells.

Scientists from the Memorial Sloan Kettering Cancer Centre suggest that cell therapy is a powerful treatment for patients who have exhausted all conventional therapies. "Our initial findings have held up in a larger cohort of patients, and we are already looking at new clinical studies to advance this novel therapeutic approach in fighting cancer." said Michel Sadelain, MD, PhD, one of the study authors, and the Director of the Centre for Cell Engineering at Memorial Sloan Kettering.

The study involved 16 patients with relapsed B-ALL who were given an infusion of their own genetically modified immune cells, called T cells. Adult B cell acute lymphoblastic leukaemia (B-ALL), a type of blood cancer that develops in B cells, is difficult to treat because and most patients who have this type of cancer experience a relapse. Patients with relapsed B-ALL have few treatment options – only 30 per cent respond to salvage chemotherapy. Without a successful bone marrow transplant, few have any hope of long-term survival.

In the study, the cells were "re-educated" to recognise and destroy cancer cells that contain the protein CD19. While the overall complete response rate for all patients was 88 per cent, even those with detectable disease prior to treatment had a complete response rate of 78 per cent, far exceeding the complete response rate of salvage chemotherapy alone.

What is cell therapy?

Cell-based, targeted immunotherapy is a new approach to treating cancer. It works by harnessing the body’s own immune system to attack and kill cancerous cells. Unlike with a common virus such as the flu, the body’s immune system does not recognise cancer cells as foreign and is therefore at a disadvantage in eradicating the disease. For more than a decade, researchers at Memorial Sloan Kettering have been exploring ways to reengineer the body’s own T cells to recognise and attack cancer. In 2003, they were the first to report that T cells engineered to recognize the protein CD19, which is found on B cells, could be used to treat B cell cancers in mice.

Last year, the same team used the therapy on five cancer patients who, remarkably, achieved complete remissions.

Currently, more studies to determine whether cell therapy can be applied to other forms of cancer are being done. Hopefully, scientists would see similar results.

The new findings were published in the journal Science Translational Medicine.