Overview and Facts about CAR T-Cell Therapy
CAR T-cell therapy, or chimeric antigen receptor therapy, is a form of individualized immunotherapy used to treat certain types of cancer. Immunotherapy focuses on using the body’s own immune system to fight cancer, and CAR T-cell therapy uses genetically modified blood T cells to find and destroy cancer cells.
T cells, or T lymphocytes, are a type of cell in the immune system that helps to cure viruses and cancer cells. They work with the B lymphocytes, or B cells, which make antibodies to fight infection, as well as directly kill infected cells in the body.
T cells help fight off bacteria, viruses, and abnormal cells, including cancers. Unfortunately, cancer cells can sometimes evade the human immune system, so T cells need to be modified to improve their effectiveness.
Currently, CAR T-cell therapy is FDA-approved for patients with adult B-cell non-Hodgkin lymphoma or childhood acute lymphoblastic leukemia. Early results of CAR T-cell therapy for treating lymphoma and other blood cancers are highly promising.
There has been over an 80% initial response rate in pediatric leukemia and adult lymphoma patients, and there are many ongoing clinical trials of CAR T-cell therapy for other forms of cancer.
For relapsed and refractory to standard therapy pediatric acute lymphoid leukemia, nearly 90% of patients will respond, and for lymphomas, approximately 60% will respond.
What to Expect with CAR T-Cell Therapy
CAR T-cell therapy is a multi-step process that consists of removing and modifying a patient’s T cells and delivering them back into the patient after laboratory modification.
First, a patient’s blood is collected and filtered through a machine to separate and remove T cells from the blood. This process is called leukapheresis, or apheresis, and usually takes 3 to 4 hours. It is the same machine and process blood donors go through when they donate platelets at a blood bank, so it is very safe.
After this, the T cells are genetically modified in a laboratory to produce special receptors on their surface, known as chimeric antigen receptors (CAR), which allow the T cells to recognize cancer cells and launch an attack to destroy them.
Once the T cells are ready, the patient receives a brief course of low-dose chemotherapy, which slightly suppresses the immune system so that it does not react to the CAR T-cells when they’re introduced into the body. Upon completion, the CAR T-cells are infused, usually over 15 minutes or less. Once the CAR T-cells enter the body, they begin multiplying, and the process of attacking the cancer cells begins.
This therapy may be given in the outpatient clinic or inpatient unit. Depending on expected side effects, patients may need to remain in the hospital or be admitted if done in the outpatient setting. Patients may remain in the hospital for several weeks to monitor their response to treatment and side effects.
Patients typically have their disease assessed approximately one month after receiving their therapy. This may take the form of a scan or a bone marrow biopsy. If the immunotherapy is successful, patients are only required to return for periodic tests and clinic visits.
What are the Side Effects of CAR T-Cell Therapy?
There are several side effects associated with CAR T-cell therapy; however, they are generally temporary and resolve with treatment.
Side effects may include:
- Cytokine release syndrome: Symptoms include high fever, chills, muscle or joint pain, headaches, nausea, difficulty breathing, and dangerously low blood pressure.
- Low blood counts: This may predispose patients to an infection. Transfusions and other medications may be necessary during the recovery phase.
- Neurologic difficulties: Symptoms include confusion, language impairment, drowsiness, agitation, and seizures.
What are the Risks of CAR T-Cell Therapy?
Complete recovery following CAR T-cell therapy can take two to three months. Although, with recent modifications, shorter recovery times may be possible. During the initial 30-day acute recovery period, patients will need the assistance of a caregiver and must be carefully evaluated for side effects and complications.
The FDA mandates that patients not drive during this 30-day period. Although most symptoms are reversible, there are several potential life-threatening risks of CAR T-cell therapy.
Loyola's CAR T-Cell Research and Clinical Trials
Loyola Medicine is the first center in Illinois to genetically modify the T cells to target and fight cancer cells in a clean lab in-house through clinical trials and research. Other centers treat patients with modified T cells developed by pharmaceutial companies.
These modified T cells are produced in the McCormick Tribune Foundation Center for Cellular Therapy in Loyola's Cardinal Bernardin Cancer Center. The center provides a super-clean environment to produce pure cell populations free of contamination from fungi, microbes and more.
In addition to producing the modified T cells in-house, Loyola will offer these cells to other medical centers in the region, across the country and even globally to help advance the science.
Learn about clinical trials and research at Loyola.
