Nevertheless, the results are remarkable, says the bone and marrow transplantation director of Abramson Cancer Center of the university, Dr. David Porter. And of the three patients still alive, two were treated more than four years ago, making them the longest running remissions in the CAR-T field.
The trained cells are not only thriving, but appear to be multiplying, the researchers at the University of Pennsylvania found, providing ongoing protection against cancer.
But in CTL019 case, the treatment seeks for lymphocytes and extracts them from the patient and improved the patient’s own white blood cells. The overall response rate was 57 percent.
“Our tests of patients who experienced complete remissions showed that the modified cells remain in patients’ bodies for years after their infusions, with no sign of cancerous or normal B cells”, said Carl June, lead author and professor of immunotherapy in Penn’s department of pathology and laboratory medicine. Only three patients are still alive with no current evidence of the bad disease after 28, 52 and 53 months respectively.
The new treatment is actually combined with conventional chemotherapy, before returning new altered T cells, a patient receives a lymphodepleting chemotherapy. Two of these subjects later died from their disease or complications of other therapies, and four are receiving other types of treatment.
The Novartis/Penn team as well as rivals like Juno and Kite and a whole pack of companies jumping into the game have been studying new technology that can be used to amp up the T cell attack on cancer cells. The cells are then reprogrammed to hunt and potentially kill cancer cells in the patient’s body. Six patients didn’t respond to the therapy, and their cancer progressed within one to nine months. Four patients experienced more severe symptoms, including low blood pressure and breathing difficulties, which required intensive care.
All patients recovered from the inflammation, including some treated with steroids.
Some of the chronic lymphocytic leukemia patients in a small-scale University of Pennsylvania study of Novartis’ CTL 109 have experienced sustained remission benefit from having the modified cells in their bodies for years after initial infusions. This means that in some patients, the re-engineered CTL019 cells retain their ability to target and destroy cancerous cells for a long period of time.
They received one treatment procedure by having CTL019, a therapy produced by the school and certified to effectively Swiss drugmaker Novartis AG.