Most people familiar with cancer treatment know of three main options: surgery, radiation and chemotherapy. But a newer option, called immunotherapy, is creating quite a buzz across the cancer community.
These drugs teach the immune system how to recognize and kill cancer cells, equipping it to home in on diseased cells while leaving healthy cells alone.
Immunotherapy comes in many “flavors.” Some you may have heard of, like vaccines and bone marrow transplants. But other types are even more cutting-edge.
“Now we’re in the era of cellular immunotherapy,” says Daniel Persky, MD, director of the University of Arizona Cancer Center Clinical Trials Office. “We’re using cells, particularly T cells, which are being retrained or redesigned to fight cancers more directly.”
CAR T cells are a form of cellular immunotherapy that gained media attention and public excitement as the first cancer treatments to alter a patient’s genes. In 2017, the FDA approved two CAR T-cell therapies in quick succession: one for patients with advanced leukemia in August, and a second for patients with large B-cell lymphomas in October.
Researchers have called CAR T cells a “living drug” because they modify a patient’s own cells to fight disease. First, blood is drawn from the patient and sent to a lab. Here, T cells are separated from the blood and “supercharged” with a gene that generates chimeric antigen receptors (CAR), which allow the T cells to bind to cancer cells and destroy them. Hundreds of millions of these T cells are synthesized in the laboratory to create a personalized, well-armed immune defense. Finally, the patient’s newly educated T cells are returned to the clinic and reinfused into the patient, seeking and destroying cancer cells in the patient’s bloodstream.
In general, immunotherapy drugs are not frequently used in pediatric populations. CAR T cells are an exception.
“CAR T cells are used to treat acute lymphoblastic leukemia, which is very common in kids,” says Emmanuel Katsanis, MD, director of the UA Cancer Center Blood and Marrow Transplantation Program.
This therapy provides a safety net for patients whose cancers return even after standard treatments.
“Bone marrow transplant still offers a cure for 75 to 80 percent of patients with acute lymphoblastic leukemia,” says Dr. Katsanis. “CAR T cells currently are reserved for patients who relapse, usually after bone marrow transplant.”
Dr. Persky is excited that the UA Cancer Center will be one of the first sites in the state to offer CAR T-cell therapy.
“We’re bringing clinical trials with CAR T-cell therapy here,” reports Dr. Persky. “We will also be opening our cancer center to standard-of-care CAR T cells.”
In the future, additional research will reveal whether CAR T cells can be aimed at solid tumors like breast and colorectal cancers. The addition of further CAR T-cell therapies to the list of approved treatments also will help patients whose cancers have relapsed. With more research, trials and FDA approvals, the future of cancer treatment is only getting brighter.
Learn more about the promise of immunotherapy in the recent issue of Act Against Cancer, in which UA Cancer Center physicians and scientists discuss their work in this exciting new field.