Biologic therapies (biotherapy) focus on the body's biological response to the tumor. 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.

  • How does the immune system work?
  • How do biologic therapies work?
  • What are biologic therapies used for?
  • What are the major types of biologic therapies?
  • What are the side effects?
  • What Are the Major Types of Biologic Therapies?

    The most common biologic therapies include:

  • Interferons (IFN)
  • Interleukins (IL)
  • Colony-stimulating factors (CSF)
  • Monoclonal antibodies (MOAB)
  • Interferons

    Interferon (IFN) occurs naturally in the body. IFN is produced by virally infected cells and is capable of protecting other cells from infection. There are three major types:

  • Interferon alpha 2a (Roferon A)—used to treat hairy cell leukemia , Kaposi's sarcoma , chronic myelogenous leukemia (CML), and other conditions
  • Interferon beta-1a ( Avonex , Rebif ) and interferon beta-1b (eg, Betaseron )—used to treat multiple sclerosis
  • Interferon gamma-1b ( Actimmune )—used to treat chronic granulomatous disease and other conditions
  • 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.


    Like interferons, interleukins (IL) occur naturally in the body and can be synthesized in a lab. Interleukins are named numerically: IL-1, IL-2, IL-3, up to IL-18.

    IL-2 has been the most widely studied in cancer treatment. This type of interleukin 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.

    Aldesleukin (Proleukin) is an IL-2 that is used to treat kidney cancer and melanoma .

    Colony-stimulating Factors

    Colony-stimulating factors (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:

  • G-CSF (Neupogen) and GM-CSF (Leukine, Prokine)—increase the number of white blood cells, which reduces the risk of infection; also used to stimulate the production of stem cells in preparation for stem cell or bone marrow transplants
  • Erythropoietin (Epogen, Procrit)—increase the number of red blood cells and reduce the need for red blood cell transfusion
  • Oprelvekin (Neumega)—increase the number of platelets and reduce the need for platelet transfusions
  • Monoclonal Antibodies

    Monoclonal antibodies (MOABs) 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 caner.

    MOABs can be used in cancer treatment in a number of ways, for example:

  • React with certain types of cancer, which may enhance the immune response
  • Be programmed to act against specific cell growth factors to interfere with the growth of cancer cells
  • Be linked to anticancer drugs, radioactive substances, other biologic therapies, or other toxins
  • Possibly help destroy cancer cells in bone marrow (during the process of bone marrow transplant)
  • There are a number of MOABs available, such as:

  • Rituximab (Rituxan)—used to treat non-Hodgkin's lymphoma
  • Trastuzumab (Herceptin)—used to treat breast cancer when the tumor expresses excess amounts of a protein called HER-2
  • Cetuximab (Erbitux)—used to treat cancers of the colon and rectum , as well as head and neck cancer
  • Panitumumab (Vectibix)—used to treat colorectal cancer
  • Bevacizumab (Avastin)—used to treat a certain type of brain tumor , kidney cancer , colon cancer, rectum cancer, lung cancer , and breast cancer
  • Alemtuzumab (Campath)—used to treat chronic lymphocytic leukemia
  • Ipilimumab (Yervoy)—used to treat melanoma
  • What Are the Side Effects?

    The side effects depend on the type of biologic therapy that is used.


    More common side effects include:

  • Flu-like symptoms (eg, chills, fever, fatigue, headache, muscle pain, joint pain)
  • Gastrointestinal effects (eg, nausea, vomiting, diarrhea, decreased appetite)
  • Other side effects include:

  • Skin—redness, rash, dry skin, itchiness
  • Heart and lungs—low blood pressure, rapid heart rate, arrhythmia , edema (fluid retention), weight gain
  • Nervous system—confusion, disorientation, drowsiness, lethargy, anxiety , depression, irritability
  • Decreased blood counts—anemia, thrombocytopenia, eosinophilia , lymphopenia
  • Problems with kidney function
  • Hypothyroidism
  • Severe toxicities are associated with high doses of IL-2.

    Colony-stimulating Factors

    CSF therapy is generally well tolerated. The side effects are minimal. Bone pain is one of the most commonly reported side effect.

    Monoclonal Antibodies

    With MOABs, allergic reaction to mouse protein is a major concern. The acute reaction can result in anaphylaxis , a severe, sometimes life-threatening, allergic reaction. This is rare, though.

    More common side effects include:

  • Fever
  • Chills
  • Sweating
  • Discomfort
  • Nausea and vomiting
  • Itchiness
  • Difficulty breathing
  • Low blood pressure
  • A delayed toxicity that can occur is called serum sickness. Symptoms of serum sickness include:

  • Hives
  • Itchiness
  • Joint pain
  • Swollen glands
  • Flu-like symptoms