In a recent issue of the journal "Science," several national AIDS experts criticize a U.S. government-sponsored clinical research trial of an AIDS vaccine in Thailand.

The 22 researchers, including Michael Lederman, professor of medicine at the Case Western Reserve University School of Medicine and director of the AIDS Clinical Trials Unit at University Hospitals of Cleveland, said that there is no "persuasive data" to suggest that the experimental combination of vaccines, ALVAC and gp120, would help to protect against HIV infection. The research trial involves 16,000 volunteers in Thailand.

According to the scientists, a clinical trial of similar design was scheduled to be conducted in the United States by the HIV Vaccine Trials Network (HVTN), the world's largest consortium of AIDS vaccine scientists and clinicians, but was cancelled last year because earlier trials had yielded weak results in terms of immune response to the vaccines.

Vaccines work by inoculating people with a small amount of a virus or portion of a virus to produce an immune response. The vaccine primes the body to recognize and fight the infection should the person be exposed
to it in the future.

The Thailand clinical trial seeks to test the effectiveness of a vaccine made from a protein found on the surface of the AIDS virus, called gp120, when given in combination with ALVAC, a vaccine composed of a harmless canarypox virus that carries several genes from HIV. The Thailand trial is a Phase III trial, which is designed to see if the combination of vaccines will prevent HIV infection or decrease the severity of the disease. The cost of the trial in Thailand is reported to be $119 million, according to the paper.

The researchers who are critical of the trial praise the National Institutes of Health's investment in basic and applied immunology research during the past 15 years and write that the "cumulative expertise gained should be used when important strategic decisions are made."

They said that the overall approval process lacked input from independent immunologists and virologists who could have judged whether the trial was scientifically meritorious.

"The scientific community must do a better job of bringing truly promising vaccine candidates to this stage of development," Lederman said, "otherwise we risk eroding public confidence in the research."

The authors of the paper are from many of the leading medical schools and research institutions in the nation, including Case, Harvard, Cornell, University of Pennsylvania, Northwestern and UCLA.

Return to the online edition of the 1-29-04 Campus News.