Biologic Therapy (Immunotherapy) for Kaposi Sarcoma

Biologic therapy, also known as immunotherapy, uses chemicals made naturally by the body (or man-made forms of these chemicals) to help the immune system attack cancer cells.

One of the first drugs used to treat Kaposi sarcoma (KS), interferon alfa, is an example of biologic therapy. For KS, interferon is injected daily into a muscle (called IM) or under the skin (called sub-q). Interferon seems to work by preventing viruses from reproducing and by activating immune system cells that attack and destroy the virus.

About half of patients with good immune function improve when given high doses of these drugs, but patients with fevers, infections, weight loss, or low CD4 counts rarely respond to interferon. Even when treatment does work, it can take several months or more to see a response.

The most common side effects of interferon therapy are flu-like symptoms (fever, pain, and weakness). Treatment with interferon can also cause low blood counts, liver problems, and confusion.

Interferon alfa is not often used now because of its side effects and because it doesn’t work well in many patients with AIDS. Other forms of immunotherapy are now being studied for use in treating KS (see What’s New in Kaposi Sarcoma Research and Treatment?).

More information on biologic therapy can be found in Cancer Immunotherapy.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: August 8, 2014 Last Revised: February 9, 2016

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