Vaccines that have previously failed to demonstrate efficacy in preventing pediatric HIV transmission may work after all, thanks to insights gained from subsequent vaccine research. Publishing their findings in The Journal of Infectious Diseases, researchers reanalyzed results from two disappointing clinical trials of pediatric HIV vaccines conducted in the 1990s.

Those vaccines had been deemed failures because they did not elicit broadly neutralizing antibodies (BNAs) against HIV among infants. However, a much more recent HIV vaccine trial among adults that found a 30 percent efficacy showed that a vaccine could protect against HIV if it elicited antibodies that attached to a particular area on HIV’s outer envelope, as opposed to eliciting BNAs. So the researchers looked to see if the two pediatric trials from the 1990s brought out this response.

The scientists found that by the time the infants were 1 year old, 59 percent of those who received a vaccine called VaxGen and 79 percent of those who received the Chiron vaccine demonstrated this particular immune response. After another year of life, 28 percent of those who received VaxGen and 56 percent of those who received Chiron still had detectable responses to the vaccine.

“It’s encouraging to find that the vaccines had induced an antibody response that lasted so long,” the study’s lead author, Genevieve Fouda, PhD, an assistant professor of pediatrics at Duke University, said in a release. “In this population of infants, where the main goal is to prevent HIV transmission from mother-to-child during the period of breast-feeding, inducing a two-year immunity would be long enough to be beneficial.”

About 260,000 infants are diagnosed with HIV annually, often through breast-feeding.

“Scientists are trying to develop new vaccines that have an even better response than those we identified in the early trials,” Fouda said. “Our work showed that vaccinated infants can make long-lasting, potentially protective antibody responses. It will be important to include infants in future HIV vaccine studies.”

To read the study, click here.

To read the press release, click here.