What are CAR T cells?
CAR T cells are the equivalent of ‘providing patients with a living cure.’ As its name suggests, T cells – which help organize the immune response and directly kill cells infected with pathogens – are the backbone of CAR T cell therapy.
Currently, available CAR T-cell therapies are tailored to each patient.
This is done by taking T cells from the patient and repopulating them in the laboratory to make egg proteins called chimeric antigen receptors or CARs.
CARs recognize and bind specific egg proteins, such as antigens, to the surface of cancer cells.
These receptors are “synthetic molecules, they do not exist naturally”, another leader in cell therapy.
After the regenerated T cells in the laboratory ‘expand’ into millions, they are returned to the patient.
If all goes according to plan, CAR T cells will continue to multiply in the patient’s body and, under the guidance of their engineered receptor, identify and kill all cancer cells secreting the target antigen.
FDA-approved CAR T-cell therapies to date target one of two B-cell antigens, CD19 or BCMA.
CAR T Cells and Cancer treatment
For decades, the basics of cancer treatment have been surgery, chemotherapy, and radiation therapy.
It remains a critical primary treatment, but new treatment categories have recently helped change the picture of cancer treatment.
The year 2000 saw the emergence of targeted therapies such as imatinib and trastuzumab – drugs that detect and kill cancer cells by eliminating specific molecular changes observed in cells.
Dozens of targeted therapies are now the standard treatment for many cancers.
And in recent decades, immunotherapy – therapies that capture and strengthen a patient’s immune system to attack tumors – has quickly become what many call the “fifth pillar” of cancer treatment.
Medicines that stimulate the immune system, in some people with advanced cancer, have the ability to reduce tumors and even eliminate them.
In a small percentage of patients, these treatment reactions can last for many years. For example, drugs called immune control inhibitors are widely used to treat people with many types of cancer, including melanoma, lung, kidney, bladder, and lymphoma.
But another form of immunotherapy, called CAR T-cell therapy, has also aroused great interest among researchers and oncologists.
Although CAR T-cell therapies are not as widely used as immune control inhibitors, they show the same ability to eliminate advanced leukemias and lymphomas and prevent cancer for many years to come.
Since 2017, six CAR T-cell therapies have been approved by the Food and Drug Administration (FDA). All are approved for the treatment of blood cancers, including lymphomas, certain types of leukemia, and most recently multiple myeloma.
Despite the excitement surrounding these therapies, they lead to long-term survival in less than half of the patients treated. They were also criticized for their cost, which was more than $ 450,000 for the most recently approved CAR T-cell therapy.
Clinical investigators reported that after years of careful research, CAR T-cell therapies have entered primary cancer treatment.
[CAR T cells] are widely available in the United States and other countries and have become the standard of care for patients with aggressive lymphoma. They have become part of modern medicine. Examples of currently approved CAR T-cell therapies include:
- Tisagenlecleucel, also known as tisa cell (Kymriah)
- Axicabtageneciloleucel, also known as axi-cell (Yescarta)
- Brexukabtageneautoleucel, also known as Brexu cell (Tecartus)
- Lisocabtagenemaraleucel, also known as liso cell (Breyanzi)
- Idecabtagenevicleucel, also known as ideecell (Alphabet)
- Ciltacabautogenous cell nucleus, also known as cilta cell (Carvykti)
Many other T-cell therapies in CAR (and similar treatments) are now being studied in clinical trials, hoping to cure other types of cancer.
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