Scientists from the Scripps Institute showed that the HIV vaccine stimulated antibody production in 97% of the subjects. The results were published in the journal Science.
The study included 48 volunteers who were not infected with HIV. A vaccine containing part of the gp120 protein that helps the virus enter cells has previously been tested on animals. 36 participants received two low-dose or two high-dose injectable vaccines two months apart. The remaining 12 volunteers, acting as the control group, received saline to counteract the placebo effect.
After the injections, all participants gave regular blood samples for 16 weeks. At the end of the study, 97% of those vaccinated had HIV-specific antibodies. Antibody levels were approximately the same in participants who received high or low doses. Two of the 12 participants who received saline were found to have antibodies to HIV at the end of the study. It’s not entirely clear why this happens – they may have developed an innate immunity to the virus when they encountered it.
98% of all participants, including those receiving saline, experienced mild side effects such as fatigue, headache, and pain at the injection site.
The authors noted that their studies did not prove that the vaccine protects against HIV infection. Also, depending on the level of antibodies produced, more than two doses are probably needed to prevent infection. But their approach could help develop vaccines against other viruses that mutate rapidly, such as influenza and dengue fever.