An HIV vaccine currently under trial has produced promising results, paving the way for a major trial to be undertaken. The news was recently announced by researchers at the International AIDS Conference, who noted that a smaller trial to test the safety of the vaccine was successful.
The large-scale trial will get underway at four locations in South Africa in November 2016 and will test the HIV vaccine on 5,400 participants, the National Institutes of Health announced. The study will include men and women ages 18 to 35 who are not infected with HIV but are at a risk for infection, and will examine whether the vaccine is safe, tolerable and effective at preventing patients from contracting HIV. Participants will receive five injections—either the vaccine or a placebo—over the course of a year. Results of study HVTN 702 are expected late in 2020.
In 2009, a trial conducted in Thailand known as RV144, produced landmark results for a similar vaccine regimen. Researchers found that after one year of vaccination, the vaccine was 60 percent effective, although the effectiveness dropped to just over 30 percent after 3.5 years. Those findings were replicated in a smaller South African trial that showed the vaccine was tolerable. The results are promising enough that the large-scale trial has been approved. This time, the design and schedule of the vaccine regimen have been changed to provide participants with more HIV protection.
“For the first time in seven years, the scientific community is embarking on a large-scale clinical trial of an HIV vaccine, the product of years of study and experimentation,” said Anthony S. Fauci, M.D., director of NIAID, part of the National Institutes of Health and a co-funder of the trial. “A safe and effective HIV vaccine could help bring about a durable end to the HIV/AIDS pandemic and is particularly needed in southern Africa, where HIV is more pervasive than anywhere else in the world.
South Africa is in the midst of an HIV epidemic. According to reports, millions of new HIV infections are reported in South Africa annually, while a subtype of the HIV virus exists in sub-Saharan Africa. The vaccine has been adapted to that HIV subtype.
“HVT 702 will tell us whether the initial success observed in HVTN 100 will bear fruit in the form of a safe and effective HIV vaccine designed for the people of southern Africa,” said Dr. Glenda Gray, president and chief executive officer of the South African Medical Research Council and lead of the HVT 702 study.
Although a vaccine is still years away from being widely available, these studies are important steps in the process, and provide hope that at some point an effective vaccine will be developed.