Understanding Immunotherapy Treatment
Immunotherapy, sometimes referred to as biologic therapy, is a newer form of cancer treatment that works to boost the patient’s immune system to fight their cancer.
The immune system is the body’s natural defense system that keeps it healthy by fighting off infections. It consists of blood cells, the lymph system (lymph nodes and ducts) and certain organs, such as the liver and spleen.
As a cancer treatment, immunotherapy uses materials created by the body or within a laboratory to help boost or restore the immune system’s function. Immunotherapy is used in certain types of advanced and metastatic cancers to find a way to control the body’s own defenses to attack its “abnormal self” in safe and predictable ways.
Using the Immune System to Attack Cancer
As a disease, cancer escapes the immune system by producing proteins that hide it. Because cancer can cloak itself, the immune system cannot find it to fight it.
One important component of the body’s immune system are cells called T-lymphocytes, which help fight any foreign proteins found within the body, such as viral and bacterial infections. These cells also help fight cancer.
As a treatment, there are three primary ways that immunotherapy can help the body fight cancer.
It can halt or decrease the growth of cancer cells.
It can stop cancer from spreading to other parts of the body.
It can improve the immune system’s ability to destroy cancer cells.
Types of Immunotherpy
As a cancer treatment, immunotherapy may include various treatment options. The following are some possible types of immunotherapy.
Monoclonal antibodies – This type of treatment is designed to attach to specific types of proteins within the cancer cells. This treatment is highly specific, so it will not affect cells that do have the targeted protein.
Oncolytic virus therapy – This newer form of immunotherapy uses genetically modified viruses to help kill cancer cells.
Non-specific immunotherapies – Instead of targeting specific types of cancer cells, this therapy enhances the immune system in a more general way, which can still lead to an improved immune response against cancer cells. It is generally administered after another type of cancer treatment, or at the same time, such as with chemotherapy or radiation. Some non-specific treatments may be given as the primary form of cancer treatment.
Cancer vaccines – A vaccine is used to help the body fight cancer, as the vaccine exposes the patient’s immune system to an antigen, which promotes the immune system to recognize and then destroy the protein within a cancer cell. These types of vaccines may be both used as a preventative or as a treatment.
About Checkpoint Blockade Inhibitors
A number of therapeutic approaches are currently being studied to harness the immune system and control cancer from spreading. One important way includes, stimulating T cells to find and destroy those hidden cancer cells. This new class of cancer drugs are known as checkpoint blockade inhibitors, as they neutralize inhibitory switches that are hardwired into T cells, usually a helpful way to prevent the immune system from turning against its own cells.
How Immune Checkpoint Inhibitors Work
An important job of the immune system is to differentiate between those cells within the body that are normal from those it sees as foreign. This allows the immune system to go after any foreign cells, without harming the normal cells. In order to accomplish this, the immune system uses checkpoints, which are the molecules on certain immune cells that need to be activated (or inactivated) to start an immune response.
Cancer cells sometimes find ways to use these checkpoints to avoid being attacked by the immune system. But new cancer drugs that target these checkpoints hold a lot of promise as cancer treatments.
These immunotherapy drugs are being studied to fight many cancers including the following:
Head and Neck
Two types of these checkpoint inhibitor drugs are Keytruda (Pembrolizumab) – the immunotherapy treatment President Jimmy Carter receives – and Opdivo (Nivolumab). These two drugs are also monoclonal antibodies,
These treatments target the PD-1 or PD-L1 checkpoint protein on T-cells. PD-1 normally works like an “off” switch to help control T cells from attacking other cells in the body. The PD-1 attaches to a PD-L1, which is a protein found on some normal as well as cancerous cells. When these two proteins bind, this signals the T cell to leave other cells alone. Because some cancer cells have large amounts of PD-L1, they are able to evade any attacks by the immune system.
Immunotherapy treatments that target either the PD-1 or PD-L1 proteins can enhance the immune system’s response against cancer cells. These treatments are showing a lot of promise in treating certain types of advanced cancers, such as melanoma
Sometimes these immunotherapy drugs used alone and at other times are given with traditional chemotherapy tratment.
Another type of check-point inhibitor is the immunotherapy drug Yervoy (Ipilimumab). This treatment attaches to the Protein CTLA-4 and stops it from working, which can help enhance the immune system’s response against the cancer cells. This drug is currently used to treat melanoma skin cancer and is being studied for use against other types of cancers.
Immunotherapy Tratment Considerations
When a patient undergoes immunotherapy treatment the patient should be mindful of the following considerations.
– The cancer could get worse before it gets better, so treatment should be continued to it’s full benefit.
– With immunotherapy treatment, the cancer might not go away, but it can be controlled a long time.
Immunotherapy should be continued for as long as there is clinical benefit and there are no serious side effects.
The following are some common forms of side effects that they patient may experience during their treatment.
Pain in muscles, bones, and joints
Shortness of breath
These more common side effects will generally become less severe after the first treatment.
Less common side effects may include:
Inflammation of the lung, intestine, kidney, liver, and brain
Problems of the thyroid
Throughout your treatment, in regards to more common side effects, your care team will provide remedies to help reduce side effects and improve your overall quality of life during immunotherapy.
It is also advised that immunotherapy treatment should not be taken by a woman if she is pregnant.
Immunotherapy Research Offering More Options
As more fundamental research unveils the secrets of the immune system and reveals how it functions, immunologists continue to discover new break-throughs that will help refine immunotherapy strategies to improve its treatment against cancer. Many of these drugs are now being tested in clinical trials, both alone and combined with other drugs.
Learn more about current clinical trials through Oncology Associates.