The T cells that is. In the huge and complex world of cancer treatment, one field of research is in CAR T cell therapy. But what exactly is CAR T cell therapy? Why is it useful, and what needs to be done to perfect this emerging field of medicine?
So what is CAR T cell therapy? An article from CancerConnect explains that it involves extracting a person’s own T cells, then genetically modified in a laboratory to give them what are known as chimeric antigen receptors (CARs) that are able to seek out and destroy cancer cells. The patient’s T cells are extracted via drawing blood, given the CAR proteins that allow them to seek out and destroy cancer cells, then transfused back into the patient en masse to attack the cancer cells. It’s like taking a bunch of your body’s soldiers and giving them the Captain America treatment where they’re cryogenically frozen for a while and brought back super buff and better able to take care of strong enemies inside your body!
As of right now, two CAR T cell therapy agents have been approved for use: Kymriah and Yescarta. Kymriah is used for people under 25 years of age with B cell precursor acute lymphoblastic leukemia, and Yescarta is approved for use on adults with diffuse large B cell lymphoma. These treatments genetically engineer CAR T cells that are able to bind to CD19, an antigenic protein found on the surface of cancerous B cells that are found in these cancers. Another CAR T cell therapy currently being investigated is Lisocabtagene Maraleucel, or liso-cel. Liso-cel is also designed to target CD19 on cancerous B cells found in lymphomas, but trials haven’t been entirely successful as of yet and has not been approved. Kymriah and Yescarta, while approved for use, are only approved for patients whose cancers haven’t responded to other treatments, or has returned after use of other treatments.
Despite CAR T cell therapy showing success in treating some lymphomas, it also has some unfortunate problems, side effects and cost. One side effect is cytokine release syndrome, or CRS. In CRS, the body responds negatively to the newly reinserted CAR T cells, resulting in high fever, blood pressure changes, and flu-like symptoms if left untreated. To address this side effect, clinics that administer CAR T cell therapy use the drug Actemra to treat CRS resulting from CAR T cell therapy. Other side effects of CAR T cell therapy include neurological effects and higher risk of infection. However, as discussed by the NCBI, these side effects and others that accompany CAR T cell therapy, like fatigue, dizziness, and pain, are side effects that also accompany other cancer treatments. Another big problem with CAR T cell therapy is the cost. The aforementioned NCBI article discusses the costs of Kymriah and Yescarta, which come out to around $511,000 and $403,000, respectively.
CAR T cell therapy is a unique and important field of research when it comes to cancer treatment. I think this could be a great new treatment for different types of cancers, especially the lymphomas already able to be treated by CAR T cell therapy. Further research should go into finding ways to prevent the harmful side effects that go along with CAR T cell therapy, as well as ways to drastically cut the cost of treatment, which being as high as it currently is, could mean the death of some terminally ill patients whose cancer is unresponsive to other methods of treatment like chemotherapy. Overall, I think this is a great step toward finding an effective treatment for different cancers as long as we can find ways to mitigate the damage caused by the treatments, both physical and financial.
Microbiology with Eric 