How CAR-T Therapy, Known As A 'Living Drug,' May Help To Kill Forms Of Cancer
A new FDA-approved cell therapy holds promise for treating a form of blood cancer called multiple meyeloma. UT Southwestern Medical Center will soon begin clinical trials of CAR-T therapy to find out if it can succeed where older treatments have failed.
Some call CAR-T (Chimeric Antigen Receptor) therapy a “living drug.”
“We're taking the T-lymphocytes or the immune cells from the cancer patient themselves into the lab [and] inserting a gene into them that codes for a protein that can then force those T-cells to recognize the cancer,” said Dr. Larry Anderson, a specialist in multiple meyeloma at UT Southwestern. “Those [cells] get infused back into the patient, and can go in and hopefully induce a remission.”
It’s not a new idea. Anderson says there have been efforts for decades to harness the power of the immune system.
“But recently with this new genetic modification technology, now we’re seeing much better response rates and deeper remissions than we’d seen with other forms of immunotherapy,” he said.
On trials for multiple meyeloma: Multiple meyeloma is a bone marrow cancer of plasma cells. One of those plasma cells can develop several mutations over a patient's lifetime, take over the bone marrow and grow uncontrollably. It can lead to bone lesions, kidney failure and anemia. We have a lot of different options for treatment, but they don’t induce long-term permanent cures or remissions, and they’re not effective for all of the patients.
On CAR-T's promise as a cure: We can’t say that they’re curing myeloma yet, but there is potential of a promise of a cure because we’ve got examples of patients who had failed many lines of treatments for their meyeloma that have received this CAR-T therapy on clinical trials. I have one such patient who had to go all the way to Pennsylvania to get his CAR-T therapy two years ago. He had failed eleven lines of prior therapy for his meyeloma, and he has been in remission for 24 months now. We don’t know for sure how long that will last, but so far it’s as much of a cure as we could hope for.
On engineering a cell to fight cancer: Currently, the companies that are working on this have it down to a pretty detailed science so that they can get a turnaround time of about four to five weeks before they can ship them back and infuse them into the patient. We certainly can’t guarantee that the disease won’t grow over a month, but at least there’s a reasonable chance that it will be stable for that short of a time compared to older methods that might take more than a couple of months to grow.
On candidates for CAR-T: On our trial for meyeloma, they’re not just fresh, brand-new patients. They’ve already had at least a couple of different lines of therapy and relapsing after that.
On side effects: The main side effect that we worry about is something called cytokine release syndrome. It can affect most patients to a low-level degree, but about a quarter of the patients may end up in the intensive care unit because of low blood pressure and high fever, and actually sometimes have to use a separate therapy to combat that cytokine release syndrome.