AIDSVAX trial disappointing

Trial results from AIDSVAX, the first AIDS vaccine to undergo phase III testing, were published this week and were disappointing. The overall efficacy of the vaccine was just 3.8% (1). The trial was conducted over three years and involved 5417 volunteers from the United States, Canada, Puerto Rico, and the Netherlands. Volunteers from high risk groups were given three vaccinations at three monthly intervals and a booster vaccination given every six months. The volunteers were split into two groups. One received a placebo and the other was given the vaccine. Twice the numbers of volunteers were vaccinated as those receiving the placebo. For those people who became HIV infected, over the three years, 5.7% were vaccinated and 5.8% received the placebo. The trial participants were counselled in safer sex and were told not to rely on the vaccine to prevent HIV transmission.