CAR T-Cell Therapy

What is CAR T-cell therapy?

Chimeric antigen receptor (CAR) T-cell therapy is a type of immunotherapy for some types of blood cancer. It works by turning your T lymphocytes (T cells) into more efficient cancer-fighting machines. In CAR T-cell therapy, healthcare providers introduce a new gene into your T cells that changes your cells so they can do more to detect and kill cancerous cells. In some cases, CAR T-cell therapy can cure blood cancer. Other times, it helps people with certain blood cancers live longer.

What conditions can CAR T-cell therapy treat?

Right now, CAR T-cell therapy is an option to treat some blood cancers when other treatments aren’t effective or the condition comes back. Those blood cancer types include:

• B-cell acute lymphoblastic leukemia (ALL).
• Diffuse large B-cell lymphoma.
• Follicular lymphoma.
• High-grade B-cell lymphoma.
• Mantle cell lymphoma
• Multiple myeloma.
• Primary mediastinal large B-cell lymphoma.

How does CAR T-cell therapy work?

To understand how CAR T-cell therapy works, it may help to know more about T cells, which are white blood cells in your immune system. Your immune system monitors your body for intruders, including cancer, by tracking proteins called antigens on the surface of intruder cells.

Your T cells have their own surface proteins called receptors. These receptors can recognize cells that have abnormal antigens. T cells act as a surveillance system for abnormal cells, becoming active when a receptor recognizes an abnormal cell. The activated T cell goes to work, destroying the abnormal cell and activating other parts of your immune system to come help find and destroy abnormal cells.

But your T-cell receptors don’t always detect cancerous cells. Enter CAR T cells, your own T cells that are changed so they recognize a specific antigen on the surface of cancer cells. Scientists change your T cells by adding a lab-made gene for a chimeric antigen receptor. Next, they make the new CAR T cells grow and multiply until there are enough cells to target cancerous cells effectively.

Once in your bloodstream, CAR T-cell receptors detect and destroy cancerous cells. The cells also keep on multiplying so you have a long-term supply of CAR T cells targeting your cancer cells. That long-term supply is why researchers and healthcare providers call CAR T-cell therapy a type of “living drug.”

Are there CAR T-cell therapies for specific types of blood cancer?

Yes, there are. Right now, there are six CAR T-cell therapies with U.S. Food and Drug Administration (FDA) approval to treat specific kinds of blood cancer. Those therapies are:

• Tisagenlecleucel (Kymriah®) to treat acute lymphoblastic leukemia in children and young adults.
• Brexucabtagene autoleucel (Tecartus®) to treat mantle cell lymphoma.
• Axicabtagene ciloleucel (Yescarta®) to treat several types of B-cell lymphomas.
• Lisocabtagene maraleucel (Breyanzi®), to treat diffuse large B-cell lymphoma.
• Idecabtagene vicleucel (Abecma®) and ciltacabtagene autoleucel (Carviykti®) to treat multiple myeloma.

What happens before I have CAR T-cell therapy?

First, you donate white blood cells through a procedure called leukapheresis. In leukapheresis, a machine draws some of your blood, extracts your white blood cells and then returns the remaining blood to your body. Typically, your providers will insert a central venous catheter to remove and return your blood.

Next, your white blood cells are quickly transported to the facility where scientists will turn your cells into CAR T cells. This process can take between three and six weeks.

Depending on your situation, you may have chemotherapy or radiation therapy after leukapheresis but before you receive CAR T cells. Your healthcare provider may call this bridging therapy. These treatments manage blood cancer during the time it takes to produce and grow enough CAR T cells to treat your condition.

When it’s time for you to receive your new cells, you’ll undergo lymphodepleting chemotherapy. This treatment keeps your body from rejecting the CAR T cells.

What happens during CAR T-cell therapy?

The actual treatment involves receiving CAR T cells via infusion. CAR T-cell infusion takes between five and 30 minutes and is done via an intravenous line (IV). You may need to stay in the hospital during the procedure. The infusion process is like a blood transfusion:

1. The CAR T cells are stored in a medical bag until they’re needed.
2. Your cell therapy nurse connects the bag containing CAR T cells to an intravenous line.
3. The new cells flow into your bloodstream.

What happens after CAR T-cell therapy?

This treatment may cause serious side effects, so your provider may recommend that you stay in the hospital immediately after treatment. Depending on your situation, including side effects, you may need to stay in the hospital for seven to 10 days. After that, you should plan to be within driving distance of your treatment center for the first month after treatment. You’ll also need:

• Someone with you 24 hours a day in case you experience side effects.
• Someone to handle driving for you for two months after you receive your T cells.

Side effects of CAR T-cell therapy

The two most common side effects are cytokine release syndrome and neurological issues. Cytokine release syndrome is an inflammatory syndrome that causes symptoms, including:

• Dyspnea (shortness of breath).
• Fever.
• Low blood pressure.
• Heart or lung issues, but that’s very rare.

Neurological issues from CAR T-cell therapy may include:

• Aphasia (difficulty speaking).
• Balance problems.
• Confusion.
• Dysgraphia (difficulty writing).
• Headache.
• Seizures.
• Tremors or twitching.

Other potential side effects are:

• An allergic reaction during infusion.
• Fatigue.
• Bruising or bleeding more easily than usual.
• Hypokalemia (low levels of potassium).
• Hyponatremia (low sodium levels).
• Increased risk of infection.

What are the benefits of CAR T-cell therapy?

CAR T-cell therapy is a newer way to treat some kinds of blood cancer when other treatments aren’t effective or when cancer comes back (recurs). Sometimes, CAR T-cell therapy can cure certain types of blood cancer. Often, it helps people live longer.

How successful is this treatment?

A 2020 study tracked children receiving treatment for acute lymphoblastic leukemia. More than 85% of the children had complete remission right after CAR T-cell treatment and 60% of those children remained free of cancer 12 months after treatment. On the other hand, an analysis of CAR T-cell therapy research concluded that for a significant percentage of people, CAR T-cell therapy wasn’t a cure for their condition.

When should I call my healthcare provider?

CAR T-cell therapy side effects can be life-threatening, especially cytokine release syndrome and some neurological issues. Before you leave the hospital, be sure to ask your provider about symptoms that could be signs of serious issues. For example, cytokine release syndrome symptoms that linger, like fever, chills, headache and nausea, may be reason to call your provider right away or go to the emergency room.