Humanosphere

Two clinical studies done in Africa, the largest done by Seattle scientists involving nearly 10,000 people in Uganda and Kenya, have shown that the same drugs used to treat HIV infection can be used to prevent the infection.

“This is huge news because of the impact it could have on prevention worldwide,” said Jared Baeton, one of the leading researchers at the University of Washington on the study, which was funded by the Bill & Melinda Gates Foundation.

“These results are tremendously exciting and confirm we are at a pivotal period in the AIDS epidemic,” said Mitchell Warren, a leading voice on HIV-AIDS prevention matters and director of the AIDS Vaccine Advocacy Coalition.

A number of earlier studies have shown that getting people who are HIV infected on anti-HIV drugs significantly reduces the risk of spreading the virus. Now, Warren said, it seems clear that people who are at high risk for HIV can also be protected if they take the drugs prior to being exposed to the virus.

The approach is known as pre-exposure prophylaxis, or PrEP. The other study cited today as demonstrating PrEP’s potential was done by the U.S. Centers for Disease Control and Prevention in Botswana involving more than 1,200 volunteers.

“This study demonstrates that anti-retrovirals (anti-HIV drugs) are a highly potent and fundamental cornerstone for HIV prevention and should become an integral part of global efforts for HIV prevention,’ said Celum, who was among the first to show the power of these drugs to prevent infection.

The UW study in Uganda and Kenya was of 4,758 “discordant” couples (in which one partner has HIV and the other does not) was called Partners PrEP and led by Celum and Baeten. On Sunday, scientific advisers monitoring the UW study ordered the placebo arm halted and the results released early.

Earlier studies of PrEP strategies had shown conflicting results, some effective and some not, but many experts say these new studies will resolve the uncertainty.

The UW study, which compared a single anti-HIV drug regimen vs a combo drug regimen, found that giving non-infected partners these drugs reduced the risk of infection by 62-73 percent (depending on if it was the single or combo drug).

But, as AIDS prevention advocate Warren noted in his statement heralding these results, science is one thing and implementing treatment or prevention programs in the real world is another.

Many millions of HIV-infected people living in poor countries and who right now need access to these drugs to save their lives are not getting them. Programs such as the Global Fund to Fight AIDS, TB and Malaria have not been fully funded by donors and governments.