Using ‘Killer’ T-cell treatment while minimizing side-effects

Researchers at the University of Pennsylvania say they are learning how to manage an experimental treatment that teaches a patient’s immune system to fight cancer. The new tricks should help them minimize side effects.

Chimeric antigen receptor (CAR) therapy, sometimes called killer T-cell treatment, is used for patients who’ve run out of other options. Penn and the Children’s Hospital of Philadelphia have posted a string of successes using it to treat leukemia patients.

“We have developed a technology where we can take a patient’s own T-cells out of their body and genetically modify them, change them, so they are now capable of recognizing their own cancer cells as abnormal,” said David Porter, director of Blood and Marrow Transplantation in Penn’s Abramson Cancer Center.

Cytokine release syndrome (CRS) is a common side effect of the therapy. CRS feels like the flu. It can be mild or life threatening.

“When it develops we have a way to stop it,” Porter said. “In some patients that therapy to stop that reaction doesn’t work, and they may get sick and sicker, despite the things we are trying to treat them with.”

The researchers say the likelihood that a patient will develop CRS seems to be linked to the amount of disease in the body.

“Patients with acute leukemia, who have a lot of leukemia in their body, almost all get a very significant CRS,” Porter said.

Three patients died of CRS after receiving killer T-cell treatment. All three people had infections in addition to their cancer. Porter says those infections may have made the side affect more severe.

Porter’s team is now exploring ways to time T-cell treatment differently in hopes of reducing those side effects.

The research group has treated more than 130 patients with the novel genetically modified T-cell approach.