Immunotherapy for Leukemia
Immunotherapy is a type of treatment for leukemia that works by prompting the body’s own immune system to identify and destroy cancerous cells. Ordinarily, the immune system protects the body against bacteria, viruses, allergens and other pathogens. However, some cancer cells can avoid destruction by tricking the immune system into treating them like healthy cells. But, by programming the immune system to locate and attack cells that have cancerous characteristics (such as certain tumor-specific proteins on their surfaces), immunotherapy can be used as a treatment for leukemia and other hematological malignancies (blood cancers).
Which types of leukemia can be treated with immunotherapy?
Not all leukemias are responsive to the same type of immunotherapy, and immunotherapy may not be appropriate for some leukemias at the present time. There are four different types of leukemia:
- Acute lymphocytic leukemia (ALL) – This is the most common form of leukemia diagnosed in children.
- Acute myelogenous leukemia (AML) – This is the most common type of leukemia affecting both adults and children.
- Chronic lymphocytic leukemia (CLL) – This is the most prevalent form of chronic leukemia affecting adults.
- Chronic myelogenous leukemia (CML) – This slow-progressing type mainly affects adults and may produce few or no symptoms for months or even years.
Most immunotherapies that are currently available are designed to treat CLL and ALL. However, new therapies are being developed every day and tested in clinical trials, so there may eventually be immunotherapies to treat all types of leukemia.
Types of immunotherapy used for treating leukemia
There are several types of immunotherapy that can be used for leukemia treatment. These include:
- Allogeneic bone marrow transplant
- Therapeutic cancer vaccines
- CAR T cell therapies
- Monoclonal antibody therapies
- Donor lymphocyte infusions
Just as all chemotherapy drugs work slightly differently, each type of immunotherapy is unique as well. T cell therapies, for instance, are used to genetically modify a patient’s T cells so that they can more effectively identify cancerous cells. Monoclonal antibodies (which are sometimes linked to toxins that can directly kill leukemia cells) target and attack specific proteins on the surface of the leukemia cell. Donor lymphocyte infusions use immune cells from a transplant donor to target cancerous cells that remain in the body after chemotherapy, while vaccines work in a similar manner but use specially created compounds to trigger an immune response.
One specific FDA-approved immunotherapy that shows great promise in treating acute lymphoblastic leukemia (ALL) is TECARTUS (brexucabtagene autoleucel). This adoptive cell therapy can be used to treat ALL that has relapsed (come back) or is refractory (not responsive to other treatments).
Side effects of leukemia immunotherapy
The side effects of immunotherapy for leukemia vary based on the type of immunotherapy delivered, the type of leukemia being treated, the patient’s overall health and additional factors. Some people experience significant side effects from immunotherapy while others do not have any side effects. However, some common side effects of immunotherapy include:
- Shortness of breath
- Skin rash
- Stomach pain
- Muscle, joint or bone pain
Some patients may experience more serious side effects, such as reactions to infusions (which are similar to allergic reactions), infections, low blood cells counts or nervous system problems such as:
- Changes in level of consciousness
- Trouble speaking and understanding speech
- Loss of balance
CAR T cell therapies can also cause cytokine release syndrome (CRS) which can be serious if left untreated. Symptoms can arise any time from a few days to a few weeks after treatment and can include:
- High fever
- Trouble breathing
- Severe nausea, vomiting and diarrhea
- Severe muscle and joint pain
- Feeling lightheaded
How does immunotherapy compare to other leukemia treatments?
As covered above, immunotherapy works by stimulating the immune system to identify and attack cancerous cells. However, there are three other main treatment modalities that are also used to treat leukemia, which work differently:
- Chemotherapy – Powerful drugs are administered intravenously or orally to kill cancer cells throughout the whole body, which is essential with blood cancer like leukemia. Chemotherapy is often used to treat AML, since it’s often widespread by the time of diagnosis. Chemotherapy for AML is typically delivered in phases, including induction therapy, post-remission therapy, central nervous system prophylaxis and maintenance.
- Radiation therapy – While radiation therapy generally isn’t a primary treatment method for leukemia since there are not usually well-defined tumors for the high-energy beams to target, it may still be used as part of an overall treatment plan. Radiation therapy can destroy cancerous cells that have spread to the spleen, spinal fluid or brain or those that have accumulated in certain areas of the body. It can also be used in preparation for stem cell transplantation, to shrink swollen lymph nodes, to reduce bone pain or to destroy cancerous cells in the trachea that can cause breathing problems.
- Bone marrow transplant – This procedure introduces healthy blood-forming cells from a donor into the patient’s bloodstream, where the cells will ideally produce healthy white and red blood cells as well as platelets.
When might a physician recommend immunotherapy for treating leukemia?
When considering immunotherapy as a treatment for leukemia, it’s important to evaluate a number of patient-specific factors to determine which option (or options) to use. At Moffitt Cancer Center, our hematologists and oncologists create individualized treatment plans that feature a wide variety of treatments. Immunotherapy may be offered as a solo treatment or in combination with other treatments (such as chemotherapy) and sometimes as follow-up to chemotherapy (i.e. “maintenance” therapy). Many types of immunotherapy are also offered in the setting of a clinical trial.
Become a patient at Moffitt Cancer Center
To learn more about immunotherapy for leukemia, call 1-888-663-3488 or submit a new patient registration form online. Our hematologists and oncologists can provide you with more information about your treatment options. A physician’s referral is not required.