By Simeon Bennett
Bloomberg News Service
AIDS drugs blocked a virus linked to prostate cancer and chronic fatigue syndrome, a study showed.
Merck's Isentress fought the virus, XMRV, more powerfully than 44 other anti-HIV compounds tested against the pathogen in laboratory experiments, according to researchers from the University of Utah and Emory University. GlaxoSmithKline's Retrovir and Gilead Sciences's Viread also prevented XMRV from replicating, according to a statement from Emory Thursday.
XMRV was discovered in 2006 and has since been found in some prostate tumors and in the blood of people with chronic fatigue syndrome. Researchers say its relationship with both diseases is unclear, and European studies last year failed to find the virus in chronic fatigue syndrome patients. Tests of the drugs in patients with XMRV are needed, said Ila Singh, who led the research at the University of Utah's medical school.
"We will need to see the results of clinical trials before these drugs can be used in a clinical setting," Singh said in the statement.
XMRV, like HIV, is a retrovirus that gets incorporated into the genome of the cells it infects. It may trigger cancer by locating in the cell's genetic material next to DNA that controls cell growth, disrupting those genes in a way that allow cells to replicate uncontrollably, Emory said in the statement.
The virus was found in 44 percent of men with the most aggressive form of prostate cancer, Singh found in a study publishedin September. XMRV turned up in the blood of two- thirds of a set of tissue samples taken from people with chronic fatigue syndrome and 3.7 percent of a group of healthy individuals, according to separate research published in the journal Science in October.
Isentress is the first in a new class of AIDS medicines that halt HIV by blocking an enzyme called integrase the virus uses to insert its genetic material into the nucleus of healthy immune cells. Merck won U.S. approval in July to sell the drug as an initial treatment for HIV patients. It was previously marketed only to patients who had failed all other therapies.
The research was published in the journal PLoS ONE, a publication of the Public Library of Science, a San Francisco-based nonprofit organization. The study was funded by Emory's Center for AIDS Research and the Department of Veterans Affairs.
Glaxo and Pfizer Inc. combined their HIV-drug units last year, with British company owning 85 percent of the resulting entity, Viiv Healthcare.
My PS: When ISENTRESS has been given with other anti-HIV drugs, the most common side effects included nausea, headache, tiredness, weakness, and trouble sleeping.