July 14, 2011

Drug Shows Promise For HIV Positive Men And Women

In the heart of the global AIDS epidemic, a breakthrough has been discovered in preventing the HIV virus from being transmitted among heterosexual couples.

The HIV prevention drug Truvada is already on pharmacy shelves but further research has established that it can help prevent infection in people not yet infected with the deadly virus.

"These studies could help us to reach the tipping point in the HIV epidemic," said Michael Sidibe, executive director of the United Nation's AIDS program, in a statement Wednesday as the study results were announced.

"This is really a game changer," Dr. Jared Baeten, the University of Washington researcher who lead of one of the studies, told the Associated Press (AP).

The research involving couples in Kenya, Uganda and Botswana with Truvada found it prevented spread of HIV to uninfected gay men. But experts were thrilled Wednesday at the first compelling evidence that AIDS medications can prevent infection between men and women.

The US Centers for Disease Control and Prevention (CDC) gave advice last fall for use of the preventive drugs among gays and is now developing guidance for heterosexuals in this country.

Dr. Michael Thigpen, lead investigator, tells Reuters that Truvada has proved to be safe and effective. The drug, he claims, along with things like male circumcision, topical microbicide gels and condoms, could be another tool for preventing the spread of HIV.

The idea of such "pre-exposure prophylaxis," known as PrEP, is gaining more credence following results of other research showing a fall in infection rates among gay men taking AIDS drugs. However, PrEP took a knock earlier this year when another study failed to demonstrate a protective effect in high-risk women.

The latest strong evidence is likely to restore confidence in the approach.

The study was funded by the Bill & Melinda Gates Foundation and run by the University of Washington and involved more than 4,700 heterosexual couples in Kenya and Uganda.

In each couple, one partner was HIV positive and the other was not. The uninfected were given either daily placebos or one of the prescription pills - Truvada or Viread.

The study found 13 HIV infections among those on Truvada, 18 in those on Viread, and 47 of those on dummy pills. So the medications reduced the risk of HIV infection by 62 percent to 73 percent, the researchers said. "Our results provide clear evidence that this works in heterosexuals," said Baeten, who co-chaired the study.

An independent review panel on Sunday said the benefit was clear-cut and stopped handing out placebos, offering instead the preventive drugs. Researchers deemed it unethical to withhold the medications from people who had been on placebo, Baeten said.

Approximately 33 million people worldwide have HIV, which causes AIDS, most live in Africa and Asia. Only about half know their HIV status, and the World Health Organization hopes that news of an effective approach to prevention will encourage more people to get tested.

Michel Sidibe, head of the UN's program on HIV/AIDS, said the new studies "could help us to reach the tipping point in the HIV epidemic."


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