Antiretroviral Drugs Could Be Used To Prevent HIV Transmission, Study Says
Antiretroviral drugs might be effective at preventing the transmission of HIV, according to a study published online in the February issue of PLoS Medicine, the San Jose Mercury News reports (Johnson, San Jose Mercury News, 2/4). For the study, Jose Gerardo Garcia-Lerma of CDC and colleagues exposed five groups of macaques to SIV, the simian form of HIV, once a week for 14 weeks.
Researchers then gave four groups various dosages and combinations of Emtriva, or emtracitibine, and Viread, also known as tenofovir. The remaining group did not receive antiretrovirals (Joshi, ANI/Topnews, 2/5). One group received a daily injection of emtracitibine, which reduced the risk of HIV transmission by 3.8-fold compared with the control group. A second group received daily oral doses of both emtracitibine and tenofovir, which reduced the risk of transmission by 7.8-fold compared with the control group. A third group of macaques received daily injections of emtracitibine and higher doses of tenofovir before being exposed to SIV, and the fourth group received the same combination before and after exposure to the virus. Walid Heneine, a CDC researcher and co-author of the study, said the combination of emtracitibine and higher doses of tenofovir provided 100% protection against SIV.
"The findings from this intermittent study suggests that ultimately it is possible to provide a promising new avenue for future research, where it opens up the floor for a lot of more research for intermittent dosing," Heneine said (Berman, VOA News, 2/5). Heneine cautioned that the formulation the monkeys received contained more tenofovir compared with the version administered to humans. He added that it is too early to know if the combination could prevent HIV transmission among humans. According to the Mercury News, other studies to test if the combination could prevent HIV in humans are under way in the U.S. and several other countries (San Jose Mercury News, 2/4).
The study is available online.