We are closer than ever to getting HIV/Aids vaccine
By Omu Anzala
The Covid-19 health crisis has captured much of the world’s attention and resources due to the resulting infections and death toll.
But we not only have Covid-19: we have the SARS-CoV-2 virus which causes Covid-19; antimicrobial resistance, where infectious agents are becoming resistant to available antibiotics; HIV that has been with us for about four decades now, and a slew of existing and emerging pathogens.
But SARS-CoV-2 has captured global attention and budgets. In the span of just five months, the US Biomedical Advanced Research and Development Authority had invested close to $4 billion in six companies working on Covid-19 vaccine research and development, according to its website.
In contrast, total estimated funding for HIV vaccine research and development (R&D) in 2018 from both public and private sources was just over $840 million.
As we move ahead to resolve SARS-CoV-2, we must also ensure we don’t leave HIV behind.
Antiretroviral drugs, aggressive testing, and inventive public education campaigns have rendered HIV/Aids a manageable disease for those with access for the last two decades.
The Global Fund approximates that of the 38 million people living with HIV, 25.4 million are on antiretroviral therapy. Better and additional tools have also been brought onboard.
We have had PrEP [pre-exposure prophylaxis], and now we have long-acting PrEP that may provide individuals with protection for up to a year.
In January, the World Health Organization recommended the use of a silicone vaginal ring containing Dapivirine as a new method for preventing HIV among women at substantial risk of contracting the virus.
Despite these expansive and expensive tools, the strides against HIV/Aids falter.
More and more people are getting infected and more than ever we need to enhance risk management as we look for better treatment and the endgame to HIV, which really is a vaccine.
Currently available treatments are not cures: they work to control the virus but they don’t eliminate it. With more infections, we have to go back and emphasise risk management.
Recent years have seen a regression. The preventive toolbox we currently have is totally dependent on behaviour (condom use, abstinence, PrEP and PEP, long-acting antiretroviral drugs) and only work when you adhere to them.
Therefore, we must be cognisant of the pitfalls of the available preventive measures even as we enhance them.
Even with treatment, there is no cure. Ideally, the endgame is to develop a vaccine that may be given once or twice.
For this to happen, funding for the HIV response, more specifically for HIV vaccine research, has to be sustained. Notably, funding for the last 10 years has been declining.
Donors have also significantly cut funding, with the UK slashing funding for the UNAIDS by 83 per cent from £15 million ($20.9 million) to £2.5 million.
But we cannot leave this to donors alone. Individual countries in low-and middle-income economies must step up their contribution towards research.
Even with funding, HIV on its own remains a complex virus which has required decades of research to understand the immune response developed by the host.
Even though the HIV vaccine journey has taken longer than we anticipated, the science developed along the way has paved a path for new innovations.
The initial works done in, and the platforms used for, HIV vaccine development have yielded fruits in the development of Covid-19 vaccines.
These include the use of viral-vectored vaccines, nucleic acid vaccines, and recombinant protein vaccines in HIV/Aids, among others.
Even if we don’t have a vaccine against HIV now, all this work has laid the groundwork for the last mile, which means that now is time to pick up the pace.
Scientists are pursuing groundbreaking research with number of vaccine strategies, including strategies to elicit broadly neutralising antibodies that target a wide range of HIV strains.
At the same time, there is also exciting work in efforts to understand if and how to cure HIV in people who are already infected. With this impetus, we can now see the finish line for an HIV vaccine.
As we mark the World Aids Day, about 40 years since the onset of the HIV pandemic, we are closer than ever to an HIV vaccine.
—The writer is professor in the Department of Medical Microbiology at the University of Nairobi