Our best shot: South African HIV vaccine shows promise
Results from a HIV vaccine trial are looking good, with people's immune systems responding well
The latest results from a small HIV vaccine trial taking place in South Africa have shown promise, revealing that people’s immune systems recognised the vaccine and responded strongly.
Whether the body’s immune system notices the vaccine and sees it as an “enemy” is one of the signs researchers look for to indicate whether or not a vaccine will work.
This is significant, with scientists saying it could lead to a more effective vaccine to prevent HIV.
According to a press release on the trial: “The early results from [the] HVTN 100 trial show stronger immune responses than some of those recorded in the [previous] Thai vaccine trial, suggesting the potential for higher levels of protection from the modified vaccine regimen.”
The trial is funded by the US National Institutes of Health, but run by two South African female scientists: Dr Linda-Gail Bekker and Dr Fatima Laher.
It is the second HIV vaccine currently taking place in South Africa.Bekker said: “These early-phase trial results show promise.”
This HVTN 100 vaccine was based on one used in a three-year study in Thailand, and that offered 31% less chance of getting the virus.
However, the Thai vaccine has been tweaked for the Southern African strain of the virus and modified to last longer and work better. Four vaccines are given to participants in a bid to make its effects last longer.
So far, the just-released results show that it will be a better vaccine than the one used in the Thai trial.
Mitchell Warren from New York-based NGO Avac said the small trial’s success showed it could continue to the next phase of study.
“The results from this trial of the modified vaccine, made especially for use in South Africa, demonstrated that the vaccine was safe, generated strong immune responses and provides the rationale for moving this vaccine combination forward into a larger trial.”
There are currently two HIV vaccine trials taking place in South Africa.
The other trial, using 5,400 participants, is called HVTN 702. It is a phase three trial, meaning that if it works, the researchers can apply for a licence for it to be used in hospitals and for it to be sold to pharmacists.
Both vaccine trials in South Africa are based on the landmark Thai trial in which the Thai vaccine reduced HIV by 60% in first year, but then protection dropped sharply to 31% less chance of getting the virus.
Researchers in both trials are working to see how the Thai vaccine can be made to be more powerful.
It is not expected that either vaccine will offer 100% protection from HIV.
HIV Vaccine Trials Network communications director Aziel Gangerdine said a vaccine was needed due to the high number of HIV infections in South Africa.“South Africa is part of a global effort responding to the HIV/Aids epidemic. It is a country with the largest antiretroviral response programme in the world. While this is commendable, there are still more than 1,000 new HIV infections in the country each day. These trials validate the commitment of the country and its people to find an effective response to curb this epidemic,” said Gangerdine.
Asked if the two vaccine trials taking place in South Africa conflicted with each other, Gangerdine said this was not the case.
“There is no conflict. Each trial is designed to answer specific scientific questions in the quest to find an effective HIV vaccine.”
In the large HVTN 702 trial, that will end in 2020, a new research site was added last week in the Eastern Cape with the researchers based at the Nelson Mandela Academic Hospital and the Walter Sisulu University. The aim is not just to increase participants, but to build scientific capacity across the nation.
“The SA Medical Research Council is committed to developing clinical research capacity in rural and underserved areas in the country. Our support of the development of this clinical trial site to conduct HIV vaccine research bears testimony to our commitment to science that is appropriate to our country,” said Professor Glenda Gray, president and CEO of the SA Medical Research Council.