March 28, 2006. Copyright, 2006, Graphic News. All rights reserved

Dual therapy could prevent HIV infection

LONDON, March 28, Graphic News: Researchers in America think theyÕre close to developing a pill that people could take to avoid getting HIV.

A cocktail of two drugs already used to treat HIV infection has shown such promise at preventing it in monkeys that officials have now said they are to expand early human tests around the world.

ÒThis is the first thing IÕve seen that I think could have a prevention impact,Ó said Thomas Folks, head of the HIV research lab at the U.S. Centers for Disease Control and Prevention.

ÒIf it works, it could be distributed quickly and could blunt the epidemic,Ó he added. The drug combination -- tenofovir (Viread) and emtricitabine, or FTC (Emtriva) -- is sold as Truvada by Gilead Sciences Inc., a California company best known for developing Tamiflu, the drug being stockpiled to treat bird flu if it jumps to humans.

In 2005, the CDC launched a $19 million study giving Truvada to drug users in Thailand, heterosexual men and women in Botswana, and gay men in Atlanta and San Francisco in the U.S.

New CDC research has shown the medication has protected monkeys from being infected with HIV. Announced at a scientific meeting last month in Denver, the research so electrified the field that private and government funders alike have been looking at ways to expand human testing.

In the experiment, six macaques were given the drugs and then exposed to a combined human-monkey AIDS virus called SHIV, using a rectal method aimed at simulating male homosexual contact.

Despite receiving doses of SHIV for 14 weeks, none of the monkeys became infected. All of another group of nine monkeys that didnÕt get the drugs eventually became infected with the virus.

What happened next, when scientists stopped giving the drugs, was equally exciting, said Folks. ÒWe wanted to see, was the drug holding the virus down so we didnÕt detect it,Ó or was it truly preventing infection? It turned out to be the latter. ÒWeÕre now four months following the animals with no drug, no virus. TheyÕre uninfected and healthy.Ó

But expense could limit use of the drug. Gilead donated its once-a-day Truvada for the studies and sells them in poor countries at cost -- 87 cents a tablet. ThatÕs more than the cost of condoms, available for pennies and donated by the truckload in Africa, but often unused. In the United States the wholesale cost of the combination drug is $650 for a monthÕs supply.

HIV spreads to 10 people every minute, 5 million every year. The World  Health Organization estimates that more than 40 million people have the virus globally.
/ENDS

Sources: Associated Press, Gilead Sciences, U.S. Centers for Disease Control and Prevention