Many of those living with HIV face a new life-threatening challenge: cancer
Unique clinical trial addresses important questions about treating cancer in those with HIV
6-Jun-2011 - CHICAGO - As the world marks the 30-year anniversary of the first reporting of HIV/AIDS, now comes the realization
of a new challenge for people with the incurable disease. For reasons not yet clear, people with HIV face a higher rate of cancers not usually
associated with HIV. This increasing rate of "non-AIDS defining cancers" includes lung, head and neck, liver, kidney, and anal cancers,
among others. The alarming uptick in cancer rates highlights the critical need to understand how to treat tumors in people taking
highly active anti-retroviral therapy (HAART) for HIV. Given what is known about HAART drug interactions, can newer targeted
cancer therapies be given safely to patients with HIV?
To explore potential interactions between HAART and the newer cancer drugs, the AIDS Malignancy Consortium (AMC),
a National Cancer Institute (NCI)-supported clinical trials group founded in 1995 to support innovative trials for AIDS-related
cancers, has conducted the first of a planned series of studies. John Deeken, M.D., a research physician at Georgetown
Lombardi Comprehensive Cancer Center and national chairman of the study, presented the findings today during a poster
session at the 2011 annual meeting of the American Society of Clinical Oncology (ASCO) in Chicago.
He says these early results already have the potential to change the way that cancer is treated in HIV patients.
"Up to this point, oncologists have not had much information about treating cancer in people taking
HAART," says Deeken. "We're basically at square one because people with HIV usually are not included in cancer clinical
trials. They're excluded because physicians are worried about causing further immune suppression in HIV patients,
and because HAART drugs are notorious for causing drug-drug interactions and serious side effects."
The first drug being studied is sunitinib. Sunitinib (Sutent®) may stop the growth of cancer cells by blocking blood flow to the tumor
and by blocking some of the enzymes needed for cell growth. However, agents in the HAART cocktail are thought to affect the same
enzymes involved in sunitinib metabolism.
The AMC chose to study sunitinib because this oral medication was approved by the Food and Drug Administration to treat kidney cancer,
which is occurring at an increasing rate among HIV patients, and the drug is being studied in other cancer types that also affect HIV
patients, such as lung and liver cancers.
Safety was examined separately for two groups within the phase I study. Group one included those whose HAART combination did not
include ritonavir, while patients in group two were taking a ritonavir-based protease inhibitor HAART cocktail.
Between August 2009 and April 2011, a total of 19 patients were enrolled, treated, and completed at least one cycle
of therapy. Sunitinib (50mg/day) was well tolerated in patients in group one - those taking non-ritonavir based HAART regimens.
Patients treated with sunitinib who were in group two, those taking the ritonavir-based therapy, experienced more side
effects including higher rates of neutropenia (compared to those reported on phase III studies of sunitinib).
"Already, we have important information that can impact treatment," says Deeken. "When the trial is complete, we may have
data to recommend that patients take different dosages of sunitinib based on what HAART cocktail they are taking. We also found that
patients could keep taking their HIV medications safely, and that sunitinib did not affect the HIV disease status of patients in
either group."
"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," says James Weihe, a community representative for the
AIDS Malignancy Consortium. "I am 60 years old and have been diagnosed with 3 minor cancers and 2 major cancers within the
last 2 years. Frequently we are rejected from clinical trials just because we are HIV positive. Dr. Deeken and the work
his colleagues are doing give us new hope. 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."
"The NCI has called for clinical trials criteria to include people with HIV though the adoption of these criteria
has been slow," says Deeken. "Here we are, years after many new and effective anti-cancer treatments have been identified and
we know so little about using these drugs in people who are also on therapy for their HIV. While the need for caution is
understandable, it may be scientifically unjustified as well as fundamentally unfair to exclude patients with HIV from clinical trials."
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The AMC study is sponsored by the National Cancer Institute under a Clinical Trials Agreement with Pfizer, Inc who provided
the sunitinib.
About Georgetown Lombardi Comprehensive Cancer Center
Georgetown Lombardi Comprehensive Cancer Center, part of Georgetown University Medical Center and Georgetown University Hospital,
seeks to improve the diagnosis, treatment, and prevention of cancer through innovative basic and clinical research, patient care,
community education and outreach, and the training of cancer specialists of the future. Georgetown Lombardi is one of only 40
comprehensive cancer centers in the nation, as designated by the National Cancer Institute, and the only one in the
Washington, DC, area. For more information, go to http://lombardi.georgetown.edu .
About Georgetown University Medical Center
Georgetown University Medical Center is an internationally recognized academic medical center with a three-part mission of
research, teaching and patient care (through MedStar Health). GUMC's mission is carried out with a strong emphasis on public
service and a dedication to the Catholic, Jesuit principle of cura personalis -- or "care of the whole person." The
Medical Center includes the School of Medicine and the School of Nursing & Health Studies, both nationally
ranked; Georgetown Lombardi Comprehensive Cancer Center, designated as a comprehensive cancer center by the
National Cancer Institute; and the Biomedical Graduate Research Organization (BGRO), which accounts for
the majority of externally funded research at GUMC including a Clinical Translation and Science Award
from the National Institutes of Health. In fiscal year 2009-2010, GUMC accounted for nearly 80
percent of Georgetown University's extramural research funding. gumc.georgetown.edu
Contact: Karen Mallet
km463@georgetown.edu
Georgetown University Medical Center
Source: EurekAlert!
http://www.eurekalert.org/pub_releases/2011-06/gumc-mot060511.php
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