A high-powerered magnification of chronic lymphocytic leukemia cells (stained in blue). A new treatment may offer better outcomes for patients who suffer from another kind of leukemia. Photo by Mary Ann Thompson
Written by Donald A. Promnitz
Valley oncologists and groups devoted to fighting cancer are optimistic about a new leukemia treatment that was recently recommended for approval by the US Food and Drug Administration.
CTL019, a CAR T-cell therapy from the pharmaceutical company Novartis, was recommended unanimously last month, and doctors in the Central Valley have taken notice. One person to welcome the therapy is Saint Agnes Cancer Center oncologist Dr. Ravi Rao — who stated that it was a profound development — comparable to “going to the moon and coming back.”
“I think it’s an exceptionally good idea. This is something that‘s been talked about for many, many decades—even in the 1960s, ‘70s… scientists were trying to figure out how to get your immune system to wake up and attack the cancer,” Rao said. “And so finally, the fact that it’s happened, to me, is like science fiction.”
“I think it’s groundbreaking for sure,” said Valley Children’s Hospital oncologist and hematologist Dr. Vinod Balasa. “If it is approved of by the FDA, it would be the first gene therapy in the United States.”
CAR T-cell therapy involves the removal of a patient’s T cells (an immune cell) and introducing chimeric antigen receptors — or CARs — to the cell that will cause them to attack their cancer. These modified cells are then reintroduced to the patient. CARs are receptors that have been engineered to graft onto the T cells.
“When the CAR T cell is put back in to the patient, it makes the T cells bind to the tumor cells and this in turn activates the T-cell to kill the tumor cell as well as force the T-cell to divide,” said Lee Greenberger, the Leukemia & Lymphoma Society’s New York-based chief scientific officer. “So in essence, a genetically engineered, tumor-killing factory has been created in the patient.”
The concept of introducing cells to fight blood cancer dates back to the early 1950s and in the ‘60s and ‘70s, researchers conceived the idea of introducing immune cells from donors to kill tumor cells in patients. In the ’80s, the receptor was discovered and the first CAR was made.
In the ‘90s and 2000s, the CAR T cell was further researched and optimized. Dr. Carl H. June pioneered the immunotherapy at the University of Pennsylvania.
“It doesn’t just come out of the blue,” Greenberger said. “There’s a lot of manipulation to find out what works.”
Over the last two decades, the Leukemia & Lymphoma Society has spent $40 million on CAR T-cell research. This includes $20 million to the University of Pennsylvania.
Currently, CAR T-cell therapy is approved for only one type of cancer — B-cell acute lymphoblastic leukemia (ALL). Leukemia is the most common form of cancer in children, with ALL being the most prevalent form. The therapy is intended for use as a last-ditch effort to kill the cancer when all other treatments have failed.
“Right now, it’s approved for just one subtype of leukemia, but the technology is scalable in that it can be scaled to other kinds of cancers,” Dr. Rao said. “So I think time will tell us how far this will go.”
Of 63 patients treated with CAR T-cell therapy in a 2015-16 trial, 82.5 percent went into remission. It is also being tested for treating chronic lymphocytic leukemia and non-Hodgkin lymphoma.
Getting the treatment into the Valley, however, will present its own challenges. While effective against leukemia, the treatment includes a number of adverse side effects, including cytokine-release syndrome (or CRS). CRS occurs when cytokines — chemical messengers that stimulate and direct immune response — are rapidly released into the bloodstream. High fevers and dangerous falls in blood pressure are the common result.
“It really requires a lot of supervision from a highly specialized team at this time, so having this treatment in the Valley is years away,” said Bethanie Mills, Leukemia & Lymphoma Society’s Central California senior manager of patient access. “However, that doesn’t mean that our Valley patients would not have access to it.”
In order to receive the treatment, a Valley patient would have to be taken to a cancer specialty hospital, where staff would be better equipped to administer the therapy and care for them as it takes effect.
Despite this, Dr. Rao said that he hopes that he will himself be able to use this treatment on his patients in time.
“I don’t really think we need more staff — I think we just need staff to be trained. We already have good cardiologists, good kidney specialists — we just need them to be on board,” Dr. Rao said. “It’s a really new branch of medicine. There’s no way people who have been trained in cardiology or infectious diseases — they have never seen the kinds of side effects and complications that happen with this. Neither have I for that matter.”
Dr. Balasa expressed his own optimism that Valley Children’s Hospital would be able to administer the treatment within a few years.
“We already do manage those kinds of problems with other kinds of treatments,” Dr. Balasa said, “so I feel that being able to treat children with CAR T-cell therapy in the future is more than likely a reality.”