A team of Harvard-led scientists is seeing positive results after testing a multi-strain HIV vaccine -- dubbed the “mosaic” -- in humans. The researchers found that every person who received the vaccine produced some kind of anti-HIV immune response, with nearly 80 percent producing more advanced responses.
For the experiment, the researchers recruited 393 healthy (non-HIV infected) adults ranging in age from 18 to 50 from 12 clinics in East Africa, South Africa, Thailand, and the United States.
The participants were divided into two groups: those who were injected with one of seven vaccine combinations (a placebo), and those who were injected with four vaccines over the course of 49 weeks. Both groups were also given an injection of the common cold virus to boost their immune systems -- once at the start of the trial and again 12 weeks in.
Five participants reported side effects that the researchers considered tolerable, including diarrhea, postural dizziness, and back pain.
Sixty-seven rhesus monkeys were also given the vaccine, and the scientists found that it protected the monkeys against simian-human immunodeficiency virus. These results lead the researchers to believe that it might also be effective against HIV.
While the researchers say these results are a step in the right direction, a new round of testing must occur to prove the drug is effective in staving off the disease in humans.
A second round of trials is now taking place on a group of 2,600 women in sub-Saharan Africa who are at risk of contracting HIV. The mosaic is one of five vaccines to ever make it this far in the testing stages, but none of the previous vaccines were successful enough to make it to the next round of testing.
Dr. Dan H. Barouch, a lead researcher on the study and a professor at Harvard Medical School, said he was “pleased” with the results but that they should still be treated with caution.
“We have to acknowledge that developing an HIV vaccine is an unprecedented challenge, and we will not know for sure whether this vaccine will protect humans,” he said.
According to UNAIDS, the United Nations program on HIV and AIDS, an estimated 1.8 million people around the world become infected with the virus every year, with about 5,000 new cases every day.
Approximately 37 million people worldwide are believed to be living with HIV or AIDS, with children accounting for two million of them..
While advancements in treatment have made exponential strides since the disease was first identified in the early 1980s, a vaccine has yet to be proven effective. However, because the mosaic vaccine attacks multiple strains of the virus, doctors would be able to administer it on a much broader scale, and it could potentially be a powerful weapon against HIV if all goes well.