UNC Lineberger Comprehensive Cancer Center researchers have successfully used an experimental safety switch, incorporated as part of a chimeric antigen receptor T-cell (CAR-T) therapy, a type of immunotherapy, to reduce the severity of treatment side effects that sometimes occur. This advance was seen in a patient enrolled in a clinical trial using CAR-T to treat refractory acute B-cell leukemia. It demonstrates a proof-of-principle for possible expanded use of CAR-T immunotherapy paired with the safety switch.