Biologic response modifiers treat metastatic kidney cancer by activating the immune system (the body’s natural defense mechanism) to fight the tumor. The term “biologic response modifier” implies that the medication does not have a direct action, but rather modifies the body’s own defense systems to help fight cancer.
Importantly, these medications do not directly kill kidney cancer cells. The idea behind these medications is that the body’s immune system naturally has some cells that are known to kill cancer cells. It is believed that the body generally does not produce enough of a response to cause regression of the metastatic kidney cancer. By giving the |
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immune system a boost, these medications aim to extend life in patients with metastatic kidney cancer. The medicines that are known as biologic response modifiers all share common side effects including fever, low blood pressure, and flu-like symptoms (all of which are symptoms related to your body’s efforts to fight the kidney cancer cells).
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Biologic Response Modifiers:
Interferon-alpha (IFN-a) has been shown to have response rates of 10-15% of patients with metastatic kidney cancer and to increase survival in some patients by a median of 2.5 months. Factors that predict a better response to IFN-a include small primary tumor (the original kidney cancer in the kidney), metastasis that are limited to the lungs or the lymph nodes only, and a good overall health prior to starting therapy. IFN-a is given 3-5 days per week as a subcutaneous injection.
Interleukin-2 (IL-2) is effective in approximately 15% of patients with metastatic kidney cancer, and, when effective, it can work quite well. Of patients treated with IL-2, 10-20% are alive 5-10 years after therapy. The downside of IL-2 therapy is the severe toxicity profile, with some studies reporting up to 4% of patients dying at least partially due to the treatment with IL-2 itself. The optimal dose and dosing frequency for IL-2 administration have yet to be determined even though IL-2 was approved for the treatment of metastatic kidney cancer in 1976. |
