AIDS Vaccine Yields Limited Protective Effect for First Time


Success with an AIDS vaccine is giving researchers some hope:

"An experiment in Thailand involving 16,000 men and women has demonstrated for the first time a small but measurable protective effect of an AIDS vaccine. The vaccine, a complicated mixture of six 'prime' and 'booster' shots, reduced a person's risk of becoming infected by about one-third compared to people getting placebo injections. The results were barely significant on statistical grounds, perplexing for scientific reasons and unanticipated by most researchers. Nevertheless, the first positive results for an AIDS vaccine after two decades of experimentation was being called a milestone."


The NYT reports: "Results of the trial of the vaccine, known as RV 144, were released at 2 a.m. Eastern time Thursday in Thailand by the partners that ran the trial, by far the largest of an AIDS vaccine: the United States Army, the Thai Ministry of Public Health, Dr. Fauci’s institute, and the patent-holders in the two parts of the vaccine, Sanofi-Pasteur and Global Solutions for Infectious Diseases. Col. Jerome H. Kim, a physician who is manager of the army’s H.I.V. vaccine program, said half the 16,402 volunteers were given six doses of two vaccines in 2006 and half were given placebos. They then got regular tests for the AIDS virus for three years. Of those who got placebos, 74 became infected, while only 51 of those who got the vaccines did. Although the difference was small, Dr. Kim said it was statistically significant and meant the vaccine was 31.2 percent effective. Dr. Fauci said that scientists would seldom consider licensing a vaccine less than 70 or 80 percent effective, but he added, 'If you have a product that’s even a little bit protective, you want to look at the blood samples and figure out what particular response was effective and direct research from there.'"

Said Mitchell Warren, executive director of AVAC, the AIDS Vaccine Advocacy Coalition: "This is a hugely exciting and, frankly, unexpected result. It changes our thinking in ways we hadn’t anticipated. We often talk about whether a vaccine is even possible. This is not the vaccine that ends the epidemic and says, ‘O.K., let’s move on to something else.’ But it’s a fabulous new step that takes us in a new direction."

An ITN video report, AFTER THE JUMP...