Paris – UNAIDS figures reveal that despite accounting for only 11 percent of the Earth’s population, Sub Saharan Africa is the epi centre of HIV/AIDS with 28.5 million of the 40 million people with HIV/AIDS coming from sub-Saharan African.
AIDS is now the leading cause of death in sub-Saharan Africa although the figure worldwide, is also high with AIDS being the fourth leading cause of death. This could be about to change with success in efforts to identify a successful vaccine.
Three HIV vaccine efficacy trials are underway in Southern Africa, and these trials are expected to define the entire design and development of HIV vaccines over the next decade revealed Professor Glenda Gray President and Chief Executive Officer of the South African Medical Council (SAMRC), and could provide effective strategies to impact on life expectancy and mortality in the region.
This is especially the case if the vaccine approaches that are being evaluated for HIV by 2021 by Southern African researchers collaborating with the NIH-funded HVTN network, are successful, stakeholders were informed at an international Conference on HIV/AIDS, STD’s and STI’s in Paris, France.
“These efficacy studies will define if either or both neutralizing and/or non-neutralizing antibodies can be tweaked to provide reasonable vaccine efficacy in high risk Clade C regions of the world,” said Glenda Gray.
She said, “The one study, called AMP, evaluating a neutralizing antibody VRC01, will determine whether the administration of VRC01 reduces acquisition of HIV infection in people who are at risk of acquiring HIV, and given the design of the study, will be able to determine the most effective dose. If so, to see if the level of VRC 01 required for protection vary by type of sexual exposure (men & women).”
The other two vaccine approaches (HVTN 702/Uhambo and HVTN 705/Imbokodo) will answer the question whether non-neutralizing anti-bodies are potent enough to achieve desirable vaccine efficacy that is durable for at least 2 years as efforts to combat HIV and develop further strategies to improve on the potency & durability.
The search for a vaccine is allegedly affected by a lack of certainty over whether it is possible to develop better recombinant proteins and adjuvants by eliciting better T helper responses to drive higher and more durable anti-bodies that are believed are necessary to curtail spread of virus.
“The difficulty in developing AIDS vaccine is that the genetic diversity of the virus is greater than any other pathogen,” observed Gray. She said, “The gp140 envelope trimeric structure is unique, hard to simulate and there are fewer trimmers on the surface than most viruses.”
There is also the problem of lack of funding for research to contain a virus that has hit Sub Saharan Africa hardest with pharmaceutical and biotechnology companies reportedly sitting on the sidelines.
“There is a reluctance to do expensive efficacy trials of HIV candidate vaccines. Almost all vaccine innovations are in the public sector,” revealed Gray.
All three trials are in full swing: with the AMP study being conducted in Southern Africa, the US and Peru. The other two trials are only being conducted in Southern Africa.
