A newer cancer drug, Sutent (sunitinib), is tolerable when paired with at least some antiretroviral (ARV) drugs in people with HIV. The study results, presented at the 2011 meeting of the American Society of Clinical Oncology, being held June 3 to 7 in Chicago, represent an important step forward, as many cancer drugs are not tested in people with HIV.

Though rates of non-HIV-related cancers are on the rise in HIV-positive people, the science isn't keeping up with this new threat. Health care providers and their HIV-positive patients who have cancer must frequently make an extremely difficult decision—stick with known, but older and less effective cancer treatments, or risk serious side effects and drug interactions with newer treatments that have never been tested in people with HIV. This is because all studies of new cancer drugs currently exclude people with HIV from their trials, and the makers of those new drugs don't generally sponsor HIV studies at later time points.

In an effort to begin addressing this problem, John Deeken, MD, from the Georgetown Lombardi Comprehensive Cancer Center in Washington, DC, and his colleagues, designed a study of Sutent—which is approved to treat kidney and gastrointestinal cancer and which has the potential for serious drug interactions with some ARV drugs.

Deeken's group treated 19 people with HIV and cancer between 2008 and 2011. All of the people were on a stable ARV regimen and completed at least one cycle of Sutent therapy at 50 milligrams per day. Sutent requires the same liver enzyme, CYP3A4, to be broken down and eliminated from the body as a number of HIV drugs—notably Norvir (ritonavir). Some of the study participants were taking ARV regimens including Norvir, and some were not.

Deeken and his team found that people on regimens without Norvir did just as well on Sutent as HIV-negative cancer patients. They were no more likely to have side effects or more severe side effects. This group also had no ill effects on their immune systems. The group taking Norvir, however, did have additional side effects from Sutent, including neutropenia, which is a loss of white blood cells and which can be more of a problem in people with HIV.

The trial is not yet complete. This first round of data was focused on how or whether Sutent could be paired with ARV drugs. Longer-term safety and guidance on Sutent dose changes will be reported when the study is finished.

“Our HIV disease is now frequently being well controlled with HAART medications, but we are still having multiple medical problems including getting cancer earlier and more frequently,” said James Weihe, an HIV-positive community representative for the AIDS Malignancy Consortium, one of the trial sponsors. “I am 60 years old and have been diagnosed with three minor cancers and two major cancers within the last two years.

“Dr. Deeken and the work his colleagues are doing give us new hope,” Weihe continues. “Their research shows that we can be included in cancer research trials if the dosages of the medications are adjusted to avoid drug-drug interactions and other side effects.”