Cellular therapies are showing tremendous promise for certain cancers previously thought to be incurable. While there are several types of cell therapies, they all remove and alter a patient’s cells, then infuse them back into the body to attack and kill cancer cells.
As part of our ongoing Conversations in Cancer video series, Diane Reedy-Lagunes, MD, a medical oncologist at Duke Health, talks to Chenyu Lin, MD, a hematologist-oncologist at Duke, who explains how they work and what the future may hold.
Duke Health experts discuss the use of cell therapy in fighting cancer.
How Does Cell Therapy Work?
Cell therapy is a personalized immunotherapy that uses T-cells, a type of white blood cell that helps the immune system fight diseases like cancer. During cell therapy, a small number of T-cells are removed from the body. They are sent to a lab where they are engineered, then infused back into the body to recognize and attack cancer cells.
What Types of Cellular Therapy Are Approved by the FDA?
Three categories of cell therapies are approved for use by the FDA. The difference lies in how the T-cells are manipulated to fight cancer.
- Chimeric antigen receptor (CAR) T-cell therapy treats leukemia, lymphoma, and myeloma that has returned. It uses re-engineered versions of the patient’s cells to find and fight cancer cells. Duke was the first North Carolina center to provide FDA-approved CAR-T therapy.
- Tumor-infiltrating lymphocyte (TIL) therapy treats advanced melanoma that has not responded to other treatments. The tumor is biopsied, and T-cells are removed. They are multiplied to large numbers in a lab, then infused back into the patient in a single dose.
- Engineered TCR T-cell therapy treats synovial sarcoma. T-cells are removed and genetically modified to produce a new receptor that enables them to target cancer cells while sparing normal cells.
How Does Cell Therapy Differ from Stem Cell and Bone Marrow Transplants?
Stem cell and bone marrow transplants restore your immune system after it’s been destroyed by high doses of chemotherapy. Healthy, immature blood-forming stem cells—either from the patient or a donor—are infused into the body after chemotherapy to generate new, healthy blood cells and a new immune system. A stem cell transplant is not an option if your body doesn’t respond to chemotherapy.
Cell therapy uses your immune system to fight the cancer. Unlike the cells used in a bone marrow or stem cell transplant, it relies on re-engineered T-cells that attack cancer cells. Because cell therapy does not require chemotherapy, it is better tolerated and more accessible.
How Are Cell Therapies Transforming Cancer Treatment?
Probably the best example is in aggressive lymphoma. In the past, when an aggressive lymphoma came back, the standard treatment would be a stem cell transplant. But many people aren’t eligible for a transplant, either because they can’t tolerate it, they are too old, the disease progresses too quickly, or it isn’t responsive to chemotherapy.
Now we can offer CAR T-cell therapies for lymphoma. The treatment can be given to older, frailer people, and doesn’t require intensive chemotherapy. As a result, cure and survival rates have increased dramatically. We’re also beginning to see evidence that people with leukemia are being cured. More data is needed but so far, it looks very promising.
What Risk Are Associated with Cell Therapy?
There are three main side effects:
- Cytokine release syndrome occurs when the body releases too much of a protein called cytokine in response to the cell therapy, causing excessive inflammation. People may experience fever, low blood pressure, and low oxygen, which is why they need to be monitored closely. We have ways to treat the inflammation, and most people do well. We are also looking into ways to minimize and prevent it.
- Neurotoxicity is also a side effect. People can become confused and experience tremors. headaches, and in more severe cases, seizures or brain swelling. Those are uncommon but can occur. Because of the risk for neurotoxicity, close monitoring is very important, and patients must have a caregiver for the first few weeks following treatment.
- Finally, some people experience a suppressed immune system, which increases their risk for serious infection. This side effect is shared among most cancer therapies that suppress the immune system, but it can last for months and even years if the immune system is weak following cell therapy.
We’re using new technology to conduct at-home monitoring of patients’ temperature and other early signs of side effects. We’re conducting trials to see if that can reduce the caregiver and travel burden.
When Should Cell Therapy Be Considered?
Cell therapies should be considered when a cancer recurs, as cell therapies are not first-line treatments. Trials are underway to determine if they will prove to be more effective than current first-line treatments.
If someone has a cancer that has returned for which there is an approved cell therapy, they should ask their doctor if CAR T or another cell therapy would be a reasonable next step. Individual circumstances might vary. Cell therapy is not right for everyone, but it certainly warrants a conversation. Much depends on the type of cancer and personal circumstances.
Why Seek Treatment at an Experienced Cell Therapy Center?
Logistically, cell therapy is very complicated to administer. You want to receive your treatment at a hospital that has an experienced team that can ensure you get through this process safely and efficiently. We’ve done more than 350 cell therapy treatments at Duke. Because we have a large transplant program, we have an extensive stem cell lab. This ensures the highest quality in processing and storing cell therapies.
In addition to hematologist-oncologists, our team includes nurses trained in protocols to manage side effects, and pharmacists who oversee supportive medications like antibiotics. We work closely to monitor and manage the side effects.
This is a very expensive treatment. Our team also includes administrative and financial staff to make sure insurance covers it.
What Is Next for Cell Therapy?
Cell therapy is a rapidly expanding field that is evolving in several different ways.
At Duke, we’re looking at how to make current cell therapies safer using certain medicines and monitoring protocols, and more effective at attacking cancer cells.
We’re also exploring different indications. For example, one Duke study is looking at whether CAR T can be used to wipe out cancer when there is so little left that it can’t be detected on a scan.
Studies are also investigating whether specially engineered cell therapies can be used to treat solid tumors like lung cancer, or even non-cancer diseases such as scleroderma, lupus, and multiple sclerosis.
