amfAR, The Foundation for AIDS Research

Important Step Forward In HIV Vaccine Research


September 24, 2009—Today’s news that an HIV vaccine candidate showed moderate efficacy in a clinical trial in Thailand represents an important step forward in AIDS research.

It is hoped that the information provided by the study can be used to inform the development of a vaccine that will one day be capable of reducing HIV infection globally.

“This study highlights the essential role of research in tackling the AIDS pandemic,” said Kevin Robert Frost, CEO of amfAR, The Foundation for AIDS Research. “The ultimate end of the epidemic will only come through research. Time and again we have seen our investments in AIDS research pay off, and today’s news is one more example of the need to expand investments in health research.”

Frost stressed that the study also highlights the role that funding for this type of research plays in the search for a workable AIDS vaccine, adding that federal funding for the U.S. National Institutes of Health (NIH) remains flat.

“The NIH, which funded much of the cost of this study, needs a significant increase in HIV/AIDS research dollars from the federal government,” Frost said. “We are not increasing funds fast enough for the kind of important work that still needs to be done.”

The trial was run by the U.S. Army, the NIH, and Thailand’s Ministry of Public Health.

More than 16,000 people participated in the trial, in which the vaccine candidate—ALVAC-AIDSVAX—conferred a modest but statistically significant protective effect. Of the 8,197 people in the trial who received the vaccine, 51 became infected with HIV, compared to 74 infections in a control group of comparable size that received a placebo. On this basis, the vaccine was judged to be 31 percent effective.

This was the first time that any HIV vaccine trial had shown any measure of protection, however small. The last major trial was stopped in 2007 when it became clear that the vaccine candidate was not only ineffective but doing more harm than good.

The relatively small numbers involved and the modest rate of effectiveness suggest that the ALVAC-AIDSVAX is not likely to be deployed in its current form. What is certain is that scientists will need to scour the data very carefully to determine the significance of the study and how it will inform the next steps along the road to a workable vaccine. 

More information about the trial results will be presented at an AIDS vaccine meeting in Paris next month.

About amfAR
amfAR, The Foundation for AIDS Research, is one of the world’s leading nonprofit organizations dedicated to the support of AIDS research, HIV prevention, treatment education, and the advocacy of sound AIDS-related public policy. Since 1985, amfAR has invested nearly US$290 million in its programs and has awarded grants to more than 2,000 research teams worldwide.