Yi Lin, M.D., Ph.D., a hematologist at Mayo Clinic and Chair of the Cellular Therapeutics Cross-Disciplinary Group in the Mayo Clinic Cancer Center spoke at the Individualizing Medicine Conference: Advancing Care through Genomics, on chimeric antigen receptor (CAR) T-cell therapy. In this new cancer treatment, cells in the immune system, known as T cells, are genetically modified to equip them to recognize and destroy cancer cells.
"We've seen very impressive results. CAR T-cell therapy is a living drug that relies on the innate ability of the patients' own immune cells to sense what's around them and to respond," says Dr. Lin. "These cells are a smart and living drug, and we hope they can last a long time in a patient's body and have a durable effect."
CAR T-cell therapy was approved by the U.S. Food and Drug Administration (FDA) last year to treat two types of blood cancer—relapsed B-cell acute lymphoblastic leukemia and relapsed B-cell non-Hodgkin lymphoma. Less than 15% of people who experience recurrence of those cancers respond completely to existing treatments. Up to 90% of people respond to CAR T-cell therapy, with 40% to 50% experiencing remission.
"Of course, this therapy is so new that we are still learning how durable that response will be," Dr. Lin says.
Other challenges remain. CAR T-cell therapy causes severe side effects that sometimes require management in the intensive care unit and, rarely, can be fatal. With support from the Mayo Clinic Center for Individualized Medicine, the researchers are working to find biomarkers that could identify individuals likely to experience severe side effects or to have a durable response to the therapy.
The researchers also hope to simplify the complex processes involved in CAR T-cell therapy to improve patients' experience. In addition, laboratory work is underway to develop a next generation of CAR T-cell therapy that would have fewer side effects and would kill other blood-based cancers and solid tumors.
Dr. Lin expects multiple myeloma to be the next cancer type to gain FDA approval for CAR T-cell therapy.
"We have a lot to learn," Dr. Lin says. "But we know CAR T-cell therapy is a good platform to develop more innovations."