New HIV Drug Blocks Disease Transmission in Mice

A new combination HIV drug may be effective in blocking transmission of the disease through two additional major routes: intravenously and anally. Previous research had only shown the drug, Truvada, to be effective in blocking HIV through vaginal transmission.

The research team, led by J. Victor Garcia−Martinez at the University of North Carolina, Chapel Hill, studied mice who had “humanized” immune systems. The strain of mice was nicknamed “BLT” because they were the recipients of human bone marrow, liver, and thymus cell transplants – which, according to the researchers, essentially “humanized” the mice’s immune systems.

The drug works by thwarting the virus’s ability replicate itself and thus infect the body. It is currently used in hospitals to treat medical workers who have been pricked by a needle that might carry the infection.

One group of BLT mice received Truvada and another served as controls. All were infected either anally or intravenously with HIV. Of the mice who had been given Truvada, only one mouse actually became infected with HIV, far fewer than the number of infected mice in the control group.

Garcia−Martinez points out that, while promising, the research did investigate mice, not humans. However, he sees great promise for the drug and envisions a time when a single, readily available pill may be used once a day to prevent transmission. Because the mice were "humanized," the study offers a reasonable view of how the virus will respond in humans.

Garcia−Martinez also notes that the drug works by thwarting the virus’s ability replicate itself and thus infect the body. It is currently used in hospitals to treat medical workers who have been pricked by a needle that might carry the infection.

Whether the drug may be available for use as a preventative measure is unclear – at present it would be exorbitantly expensive to do so. The researchers also note the possibility that it might offer people a false sense of security and promote unwarranted promiscuity – a particularly dangerous scenario, since it might not be 100% effective at HIV prevention.

While more research is being done to learn about the drug’s efficacy, safe sex (or abstinence) is unequivocally the best practice for HIV prevention now. The research was published Jan. 21 in the online journal PLoSOne.org.