What’s New in Kaposi Sarcoma Research?

A great deal of research is being done to find more effective ways to prevent and treat Kaposi sarcoma (KS).

Prevention

Probably the most important advance in the prevention of AIDS-related KS has been the development of drugs that help control HIV infection and AIDS. This has reduced the chance of getting KS.

Testing for Kaposi sarcoma--associated herpesvirus (KSHV), the virus that causes KS, could help manage patients at risk for KS, including those who are HIV-positive or those who will be having an organ transplant and will be taking drugs to suppress their immune system.

Newer drugs, such as valganciclovir, used to treat related herpesviruses such as cytomegalovirus (CMV) can also help treat KSHV infections. These drugs stop the KSHV-infected cells from making more of the virus, although they haven’t been found to help treat KS once it has developed.

Treatment

Researchers are studying new and different ways to treat KS.

KS lesions depend on the formation of new blood vessels for their growth. Drugs called angiogenesis inhibitors, which block the growth of blood vessels within tumors, may help treat these lesions. For example, the drug bevacizumab (Avastin^®) has been shown to cause some KS lesions to shrink or stop growing in a small study. This drug and other angiogenesis inhibitors, such as sirolimus and everolimus, are being studied further.

Drugs called immunomodulating agents both boost the immune system and affect blood vessel growth, so these drugs may be helpful against KS. The oldest of these drugs, thalidomide (Thalomid^®), has been shown to help shrink some KS lesions in early studies, but this drug can have side effects that make it hard to take. Related drugs, such as lenalidomide (Revlimid^®) and pomalidomide (Pomalyst^®), which tend to have fewer side effects, are now being studied.

Some other drugs that are already used to treat other cancers are also being studied for use against KS, including bortezomib (Velcade^®), imatinib (Gleevec^®), and sorafenib (Nexavar^®).

Research into HIV vaccines and antiretroviral drugs also may have a great impact on AIDS-related KS.

KSHV also offers a new target for KS drugs and biologic therapy. Clinical trials are testing whether antiviral drugs that target KSHV may be used for KS.