A new HIV vaccine trial has begun in Johannesburg, South Africa where experts are cautiously optimistic about its potential for success.

The trial, which is funded by the National Institutes of Health, is based on a trial that took place in Thailand and yielded moderately successful results. Thailand trial’s results were controversial because the vaccine was tested on a segment of the population with a low risk for infection. The trial in South Africa hopes to remedy this issue by using members of their own population, which have a uniquely high rate of infection and thus puts wider swaths of the population at risk.

The HIV/AIDS death rate has greatly decreased with the increasingly widespread availability of antiretrovirals, yet infection rates continue to increase. Scientists and doctors believe that a vaccine is the only possible measure to successfully eradicate the disease, and many of them believe that this trial could be the beginning of the end for a disease that continues to infect more than 1,000 people daily in South Africa alone.

CNN reports that an estimated one adolescent becomes infected every two minutes worldwide. According to Anthony Fauci, the director of the U.S. National Institute of Allergy and Infectious Diseases, there is no reason to believe that the HIV/AIDS crisis is over. In the U.S., infection rates have remained steady for the past 15 years in spite of prevention efforts.

Because of the high HIV infection rate in South Africa, scientists believe that an effectiveness rate of 50-60 percent would be sufficient to enter negotiations with drugmakers, although this is significantly lower than most other vaccines.

The study will enroll 5,400 sexually active men and women between the ages of 18 and 35 who are not infected with HIV. They will receive five shots of the vaccine and three boosters over the course of the study, which is expected to yield results in 2020. It aims to provide greater protection from infection and has been adapted for the HIV subtype that is found in southern Africa.

This trial, which is the first HIV vaccine trial in nearly a decade and is only the seventh full-scale human trial in the world, has been met with both skepticism and optimism. Glenda Gray, the president of the South African Medical Research Council, is leading the study. Although she admits that there is no guarantee that the trial will be successful, she remains optimistic about the results.

The HIV vaccine trial in Thailand was run by the U.S. Army, whose Dr. Nelson Michael called the trial “A signpost for vaccine development. This was a yes-we-can moment: the opportunity to become enthusiastic. The door has cracked open. We are all going to try to collectively crash through it.”

Kenya, who will be monitoring the trial closely, is expected to begin a similar trial early next year.

– Eva Kennedy

Photo: Flickr