CAR T gene therapy, also called CAR T-cell therapy, is a type of immunotherapy. It uses your own immune system -- the germ-fighting system of your body -- to attack specific cancer cells.
Doctors call it a “living drug,” because it’s a treatment made with modified working cells in your body instead of man-made compounds. The FDA approved it for use on primary mediastinal B-cell lymphoma in the fall of 2017.
CAR stands for "chimeric antigen receptor." Scientists make it in a lab and add it to immune cells called T cells. It makes them able to “see” your lymphoma cells and attach to them, like a key fitting into a lock. Once these CAR T cells latch on to the cancer cells, they can destroy them.
How You Get It
From beginning to end, CAR T-cell therapy can take several weeks. In order to add CAR to your T cells, your doctor will first remove the T cells from your blood. To do this, you’ll be hooked up to two IVs -- one to take blood out of your body, and one to put it back into your body after a machine separates out your white blood cells. While that happens, you’ll lie down on a bed or recline in a chair. A session takes 2 to 3 hours, and you’ll need to be still.
Lab workers separate the T cells from your white blood cells after they’re out of your body, and then add the receptors to them. Then, they multiply the altered cells for about a week, freeze them, and send them back to the place you’ll get your treatments.
Before a doctor puts the modified cells back into your body, they may have you take a low dose of chemotherapy. This is so you'll have less of the other immune cells in your body, which gives the new T cells a better chance to turn on and work.
You’ll get T-cell treatment through an IV. It’s a one-time process that’s a lot like a blood transfusion. You’ll be admitted to a hospital for it. How long you stay there depends on how you react to the infusion.
Your doctor will likely ask you to stay within 1 to 2 hours driving distance from the center where you get your treatments for about 30 days after your infusion. That's so they can monitor you as you recover.
Possible Side Effects
During the blood removal process, your calcium levels may drop. That can make you feel numb and tingly, or give you muscle spasms. Your doctor can help treat this side effect by giving you calcium by mouth or through another IV.
After the CAR T cells are working and multiplying inside your body, you may get a condition called cytokine release syndrome (CRS). It can be mild or severe, and can feel like the flu. It may cause:
- High fever
- Dangerously low blood pressure
- Fast heartbeat
- Trouble breathing
CAR T-cell therapy could also affect your brain and cause:
- Bad headaches
More studies are being done to figure out if CAR T gene therapy can cure primary mediastinal B-cell lymphoma. For some people, CAR T cells may go away once the cancer has been in remission for a long time. Doctors are still studying its long-term treatment effects.