Scientists Present Vaccine That Reduces AIDS Infections by 31%

By Dialogo
September 28, 2009

Following tests in 16,000 volunteers, a group of scientists from the United States and Thailand presented today in Bangkok a vaccine that reduces the risk of AIDS infection by 31.2 percent, marking the first time that it has been possible to slow the spread of the disease with measures of this kind. “These results show that development of a safe and effective preventive HIV vaccine is possible,” emphasized Col. Nelson Michael, director of the Division of Retrovirology at the Walter Reed Army Institute of Research and of the U.S. Military HIV Research Program. These results are very encouraging, although more studies are needed, the military officer added in a press conference in Bangkok. The experimental vaccine was presented in the Thai capital by members of the group that collaborated on the research: the U.S. Army, the Thai Health Ministry, the U.S. National Institute of Allergy and Infectious Diseases (NIAID), Sanofi-Pasteur, and Global Solutions for Infectious Diseases. Dr. Anthony Fauci, director of NIAID, warned against getting carried away, but said that “I don’t think there’s any doubt that this is a very important result,” after twenty years without progress. The experimental vaccine is known as RV144 and mixes two genetic formulas that had not previously been effective in humans and that on this occasion protected 31.2 percent of the volunteers who were inoculated with the new combination. The study began in 2003, involved 16,402 volunteers - men and women between eighteen and thirty years old - and started by giving half the group the vaccine and the other half a placebo. Among those who received the placebo, seventy-four individuals became infected; among the others, only fifty-one. Dr. Fauci indicated that scientists normally consider a vaccine feasible when its level of effectiveness is above 70 percent, but in the case of AIDS, any protection is already progress. A more detailed report on the clinical trial will be presented at the AIDS Vaccine Conference to be held in Paris from 19 to 22 October.