If the progress we see today is anything to go by, it means we are closer than ever to having an HIV vaccine.
COMMENT
On May 18 1997, United States President Bill Clinton committed to developing an HIV vaccine within 10 years. Nearly 20 years later, we still don’t have one. And every day in South Africa, more than 1 000 people become newly infected. Young women and girls are especially hard-hit by HIV in our country.
But HIV vaccine advocates do have a lot to celebrate with regard to vaccines, and also HIV prevention generally, especially in South Africa.
For much of the first 30 years of the epidemic, there have been essentially two strategies to prevent sexual transmission of HIV: abstinence and condoms.
But in the past decade, we’ve had important advances. For example, we now know that antiretroviral drugs not only keep HIV-positive people healthy, they also work so well that a person on successful HIV treatment has very little chance of passing the virus on to a sexual partner. Treatment is also prevention.
Male circumcision, in which the foreskin of the penis is removed, also works to reduce a man’s risk of acquiring HIV; fewer HIV-positive men mean less HIV risk for women and the population at large. In addition, multiple studies of pre-exposure prophylaxis (PrEP), or preventive treatment – some of them here in South Africa – have shown that men and women at risk of HIV can take a particular type of antiretroviral medication to prevent infection, if they take the pills consistently.
But too many South Africans – especially young girls – don’t realise their risk of HIV, or don’t know what is available to prevent infection. The first step is to give prime-time attention to messages about all these new methods – what they are, how they work, how to get them – and how to know whether you are at risk. For example, a lot more still needs to be understood about how PrEP could be made available in South Africa. At the same time, we need to continue investing in research that will find more and better prevention methods, especially a vaccine.
Vaccine needed to end HIV
An HIV vaccine remains essential to ending the epidemic.
In 2009, in a clinical trial in Thailand, an experimental vaccine showed some success in reducing the risk of HIV transmission.
And earlier this year a trial to test a modified version of that vaccine – redesigned with the goal of making it more protective – started in South Africa. If this trial has positive results, in two years a large-scale efficacy trial would begin, which could eventually lead to a licensed vaccine.
Further upstream, research involves the discovery that some people living with HIV create particularly potent antibodies able to “neutralise” many different HIV strains.
A handful of these “broadly neutralising antibodies”, or bNAbs, have been isolated from blood samples donated by HIV-infected individuals, including women, from a trial here called Caprisa 004. Broadly neutralising antibodies target multiple HIV-1 viral strains and, as opposed to non-bNAbs, are specific to individual viral strains. Scientists are now planning to test whether direct transfer of the most potent antibodies could prevent, treat or even be part of a cure for HIV when infused directly into the bloodstream.
Scientific research, academic meetings and journals have been buzzing with talk about bNAbs for the past few years, especially in the vaccine research community.
But the reality is that bNAb research is in the very early stages, there are many questions and unknowns, and the science is extremely difficult to understand and explain to non-scientists.
Civil society input
As this work moves forward, scientists and funders need to collaborate with advocates and citizens to ensure that adequate resources are allocated to communications and civic engagement.
With all of the excitement about bNAbs and two different vaccine strategies now entering clinical trial phases in Southern Africa, the robust community of African HIV researchers must be at the table before decisions are made.
HIV activists, advocates and community stakeholders who will need to explain the science, purpose and possible outcomes of this research need support to track the research path, ask the hard questions, demand progress and conduct other aspects of the research and development process. Active involvement of our government in driving and funding clinical research also needs close attention.
If the progress we see today is anything to go by, it means we are closer than ever to having an HIV vaccine. But funding is finite and only the most promising strategies should move ahead.
The HIV vaccine field needs to develop a transparent decision-making process that directs efforts towards only the likeliest candidates for success. And that decision-making process must include the people who really need an HIV vaccine.
Ntando Yola is a former HIV Prevention Research Advocacy fellow and works for the Desmond Tutu HIV Foundation in Cape Town.
