The results of the world’s first phase 3 HIV vaccine efficacy trial are reported in the March 1 issue of The Journal of Infectious Diseases, now available online. Although the vaccine was ineffective in preventing HIV infection, the trial represents a landmark in the fight against HIV and offers the scientific community a foundation on which to build future trials.The multi-centered trial, conducted in the United States and the Netherlands and completed in 2003, is described in two papers by the rgp120 HIV Vaccine Study Group, and Peter B. Gilbert and colleagues, which address the vaccine efficacy results and the immunologic responses of the study participants.The vaccine, produced by VaxGen, was a recombinant construct of the HIV envelope glycoprotein, similar to the type of vaccine used to develop a vaccine for hepatitis B. The vaccine was tested in a double-blind, randomized study of healthy participants who did not use intravenous drugs. The volunteers were men who have sex with men or women at high risk for heterosexual transmission. The vaccine and placebo were given by injection seven times over 30 months and the participants were assessed for risk. At each visit the participants were tested for HIV infection, and for those who were positive, HIV-1 plasma RNA load and CD4 cell counts were monitored on a regular basis for 24 months after the initial diagnosis.
