An experimental HIV vaccine failed a key trial in South Africa
A vaccine designed to prevent human immunodeficiency virus infection has proven no better than a placebo during a trial in South Africa. The National Institute of Allergy and Infectious Diseases in Bethesda, Md., announced the results on February 3, citing an analysis by an independent review board. The news is disappointing, but also increases scientists’ resolve to develop an effective vaccine, says Barton Haynes, director of the Duke Human Vaccine Institute at Duke University School of Medicine in Durham, N.C., who was not involved in the clinical trial. The Phase III trial included more than 5,400 sexually active men and women, ages 18 to 35. Trial participants were given six injections of vaccine or placebo over 18 months. An interim analysis in January found that the risk of becoming infected with HIV — the virus that causes AIDS — was the same whether a participant received the vaccine or the placebo: 129 new infections occurred among the vaccinated group of 2,694,...