While a lifetime vaccine for HIV still remains unavailable, a major breakthrough experiment using a different technique paves the way for effective long-term protection against the deadly virus.
“This might turn out to be a seasonal alternative to a vaccine until we really know how to make one,” said HIV researcher Malcolm Martin of the US National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, the lead author of a new study published in Nature.
A vaccine activates the organism’s own defense, so that it begins producing antibodies that fight a disease. But in this case, American and German scientists injected ready-made antibodies which were produced by infected humans and then processed in a lab.
During the trial study, a group of macaques were exposed to doses of HIV, and its simian equivalent SIV, with scientists noting that the animals became infected within two to six exposures.
Four groups of other healthy macaques were then given various formulations of antibodies, then exposed to the disease once a week.
Results were notable: depending on which antibodies they were given, the monkeys managed to stay healthy through 12 to 23 weekly exposures, with risk gradually growing as the concentration of antibodies in the bloodstream declined.
“The result is surprising,” Ruth Ruprecht, director of the AIDS Research Program at Texas Biomedical Research Institute, who was not involved in the study, told The Verge. “I am astonished by how long protection lasted.”