Immunotherapy for Kaposi Sarcoma

Immunotherapy, uses chemicals made naturally by the body (or man-made forms of these chemicals) to help a person's 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 intramuscular; IM) or under the skin (called sub-q; subcutaneous). 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 (white blood cells) 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 cell counts, liver problems, and confusion.

Interferon alfa is not used often now because of its side effects and because it doesn’t work well in many patients with AIDS.

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

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Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

National Cancer Institute Physician Data Query (PDQ): Kaposi sarcoma treatment - Health Professional Version. 01/30/2018. Accessed at accessed on March 12, 2018.

National Comprehensive Cancer Network (NCCN)—AIDS-Related Kaposi Sarcoma. V1.2018 (11/03/2017). Accessed 03/02/2018 from

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Yarchoan R, Uldrick TS, Polizzotto MN, Little RF. Ch. 117 - HIV-associated malignancies. In: DeVita, Hellman, and Rosenberg’s Cancer: Principles & Practice of Oncology. 10th ed. Philadelphia: Lippincott Williams & Wilkins; 2015.

Last Medical Review: April 19, 2018 Last Revised: April 19, 2018

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