/ 17 May 2016

HIV vaccine – closer than ever

Hiv Vaccine – Closer Than Ever


On 18 May 1997, Bill Clinton, then president of the United States, called for a “new national goal for science” to develop a vaccine for HIV in a decade. Almost two decades later advocates and researchers will once again mark the day with messages and updates on what has come to be called HIV Vaccine Awareness Day. We mark the date each year because of the hope research continues to give us for a possibility to end HIV: there have been multiple discoveries and new insights about the virus that make the prospect for a HIV vaccine more feasible with each passing year. 

Two years after Clinton’s call for a focus on vaccine research, the South African government made a significant investment in HIV vaccine research, the first major commitment from an African country.  Today HIV vaccine research programmes and clinical research in Thailand, Kenya, Nigeria and several other countries are working on dozens of approaches to find a safe and effective HIV vaccine.  

New findings
This May 18 is more important than ever as we celebrate the many new findings that built on the success of the Thai trial, RV144. In 2009, RV144 showed modest efficacy – enough to prove that an HIV vaccine is possible and to offer clues to how researchers might develop a more effective, licensable one that could have a major effect on the epidemic. 

Seven years after that glimmer of efficacy, the US National Institute of Allergy and Infectious Diseases announced on this week on HIV Vaccine Awareness Day, on behalf of an international group of partners, that a modified version of that vaccine will move to a large-scale efficacy trial in South Africa later this year.  

That means that more than 5 000 South African men and women will be asked to join tens of thousands of others around the world who have rolled up their sleeves for experimental jabs, in the hope of finding a vaccine to help end the worst epidemic in human history.

If this new trial goes ahead this year, more than 5 000 South African men and women will be asked to join tens of thousands of others around the world who have rolled up their sleeves for experimental jabs, in the hope of finding a vaccine to help end the worst epidemic in human history. That’s news worth celebrating. A study of another vaccine product, developed by US pharmaceutical company Johnson & Johnson is also promising. This vaccine may also move to the field for testing in the coming year or so if data from earlier stage trials continues to look encouraging. That means when we celebrate the next HIV Vaccine Awareness Day, there could be thousands more people working with researchers to find an effective vaccine.  

Read our comment piece on HIV vaccine and decision-making here.

Efficacy of trials
We know there’s a chance that these vaccine strategies won’t be deemed good enough to give the answers of effectiveness we are looking for. And that even if one or both does, there’s a chance they won’t be effective in large trials or be licensed for use in public health settings. While we wait to see if these two efficacy trials progress, researchers have begun a different kind of study in North and South America, with a companion study slated to begin soon in East and Southern Africa. 

The antibody-mediated prevention (AMP) will look at whether an infusion of a broadly neutralising antibody, known as a bNAb, delivered every eight weeks can prevent HIV infection. Researchers have discovered hundreds of different bNAbs over the past few years in the blood of HIV-infected people, who produce them naturally. In laboratory studies, these antibodies effectively block many different strains of HIV from infecting human cells. With the AMP studies, researchers have redesigned the bNAbs to see if they can block HIV infection. The result of the AMP studies won’t be a new prevention option, but will instead answer some of the key questions that researchers have about how to construct an HIV vaccine that could train the human immune system to develop these antibodies on its own. 

It’s a different concept for an efficacy trial to we are used to, but these are important and exciting studies in search for new HIV prevention options. The one question we get more than any other is: “When will there be an HIV vaccine?” If science missed Clinton’s deadline, how many more years or decades must we wait? The truth is, we don’t know. Even if one of these promising strategies is eventually proven effective, positive results are just the beginning of making a vaccine available to those who need it. Moving from results to licensure, manufacturing and rollout plans can add several years to the process. 

Read our piece on anti-vaxxers here.

Measuring progress
So we know that we will continue to mark this day and measure the progress toward a safe, effective, licensed and available HIV vaccine for many years to come. With each HIV Vaccine Awareness Day, we balance optimism with a reminder that the path we are on is long and winding. This year in particular, we mark the day with hope, optimism, and a renewed sense of purpose to work alongside researchers, funders and policy makers along with trial participants and their communities to ensure that we are moving along the path with focus, determination and relative speed.  

We echo the words of Minister of Science and Technology Naledi Pandor at the inaugural Research for Prevention Conference in Cape Town in 2014: “We remain many years away from eliminating HIV as the epidemic continues to outpace our efforts to control it. The number of newly-infected people each year continues to outnumber those who gain access to treatment. We need new prevention tools if we are to escape this epidemic. Investment in research and development for new prevention tools remains a critical goal for us all.” And finally, we celebrate and acknowledge the role played by all those women and men, who join forces and participate in HIV vaccine trials. They show us it is only through a collaborative process of communities, scientists and governments that we shall be able to find an HIV vaccine.  

Tian Johnson works for the African Alliance for HIV Prevention in South Africa, Ntando Yola works for Prevention of HIV and Aids (APHA) at the Desmond Tutu HIV Foundation in South Africa, Morenike Folayan works from the New HIV Vaccine and Microbicide Advocacy Society in Nigeria, Udom Likhitwonnawut is from the National Community Advisory Board on Biomedical HIV Research in Thailand and Matthew Rose is an HIV prevention advocate from the United States.