Biologic therapies uses the body's own systems and abilities to fight the cancer or heal healthy tissue after treatment. Most of these therapies take advantage of the body's immune system, either directly or indirectly, to fight cancer or to lessen the side effects that may be caused by some cancer treatments.
The immune system consists of a complex network of cells and organs. The key cells involved in the immune system are white blood cells which signal, identify, and attack infectious invaders. There are several types of white blood cells, each with their own function including:
Cells release proteins called cytokines. These cytokines are important communicating factors between cells to help boost the immune system and identify good or bad cells. Cytokines include:
Biologic therapies repair, stimulate, or enhance the body’s response to cancer. Biologic therapies can:
Biologic therapies are most commonly used either to treat cancer that does not or has not responded to other forms of treatment. They may also be used to treat tumors that may respond to the body’s own immune defenses.
The most common biologic therapies include:
IFN occurs naturally in the body. IFN is produced by virally-infected cells and is capable of protecting other cells from infection. Researchers have found that interferons enhance the immune system’s ability to fight cancer cells and act directly on these cells by slowing growth and encouraging normal cell behavior.
There are different types of IFNs, but interferon alpha is used to treat cancer. Currently interferon alpha is used to treat cancers including hairy cell leukemia, Kaposi's sarcoma, and chronic myeloid leukemia (CML).
Like IFNs, ILs occur naturally in the body and can be synthesized in a lab. ILs are named numerically as IL-1 through IL-18.
IL-2 has been the most widely studied in cancer treatment. This type stimulates the growth and activity of many cancer-killing immune cells, including NK cells and cytotoxic T cells. In addition, IL-2 enhances antibody responses.
CSFs do not affect cancer cells directly. Instead, CSFs help stimulate the production of new red blood cells, white blood cells, and platelets. This is important because many cancer treatments can decrease the levels of blood cells, which increases the risk of infection, anemia, and bleeding problems. Stimulating blood cell production can help stimulate the immune system.
Some examples of CSFs include:
Monoclonal antibodies (mAbs) are substances that are produced in a lab. The process involves injecting a mouse with cells for a certain type of human cancer. Once injected with the cancer cells, the mouse produces antibodies to fight against the cancer. These mouse antibodies are then combined with other lab cells to create hybrid cells to fight cancer.
MAbs can be used in cancer treatment in a number of ways. They may:
There are a number of mAbs available, such as:
The side effects depend on the type of biologic therapy that is used.
At the beginning of therapy, you will most likely experience flu-like symptoms, such as chills, headaches, muscle and joint pain, and discomfort.
Chronic side effects tend to increase in intensity after you have been on IFN therapy for several weeks. Loss of appetite with weight loss and fatigue can be severe enough to limit the dose. Other side effects include:
More common side effects include:
Other side effects include:
Severe toxicities are associated with high doses of IL-2.
CSF therapy is generally well tolerated. The side effects are minimal. Bone pain is one of the most commonly reported side effects.
With mAbs, allergic reaction to mouse protein is a major concern. Rarely, the acute reaction can result in anaphylaxis, a severe, sometimes life-threatening, allergic reaction.
More common side effects include:
A delayed toxicity that can occur is called serum sickness. Symptoms of serum sickness include:
Biological therapies for cancer. National Cancer Institute webite. Available at: http://www.cancer.gov/about-cancer/treatment/types/immunotherapy/bio-therapies-fact-sheet. Updated June 12, 2013. Accessed December 27, 2016.
Biological therapy for lung cancer. Cancer Research UK website. Available at: http://www.cancerresearchuk.org/about-cancer/type/lung-cancer/treatment/biological-therapy-for-lung-cancer. Accessed December 27, 2016.
Biologic therapy: The basics. OncoLink website. Available at: http://www.oncolink.org/treatment/article.cfm?aid=589&id=335&c=16. Updated September 28, 2016. Accessed December 27, 2016.
Modalities of cancer therapy. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/hematology-and-oncology/principles-of-cancer-therapy/modalities-of-cancer-therapy. Updated July 2013. Accessed December 27, 2016.
Last reviewed December 2016 by Mohei Abouzied, MD Last Updated: 5/26/2015