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Every person mistakes the limits of their field of vision for the limits of the world

This July, Durban played host to their second International AIDS conference. This is the biggest and most publicised of the HIV conferences, with the likes of Elton John and Prince Harry showing up to support the cause. This meeting is not really recognised for its pure scientific nature, but is regarded in our lab as something everyone should attend at least once. The goal of the meeting is really to bring social issues to the fore: interventions, activism and policy to improve the lives of those affected. Ultimately for basic scientists, it’s about gaining a wider perspective about the work we do, the impact we make and to motivate us to work harder to lighten the burden South Africa has borne for so many years. But the world of activism, especially celebrity activism, is also a world that could learn from science.

Charlize Theron spoke at the conference saying several things that upset me. The media raved about her speech saying she certainly didn’t sugarcoat anything – as if we don’t know how bad the epidemic is already. I think one of the things that upset me most was this, “The real reason we haven’t beaten the epidemic boils down to one simple fact: We value some lives more than others.” I do not deny that this is a very real issue in the world today; but I truly don’t agree that this is why we haven’t beaten the epidemic. It is easy to get swept up in this statement and feel some guilt as a privileged and fairly happy PhD student who lives life with a clean bill of health (apart from sleep deprivation), but I am worried that a statement like this really works against scientists.

There are legitimate and horrifying biological challenges that we face with this formidable foe. HIV adapts so rapidly our immune systems can’t keep up. About 20% of people develop amazing antibodies that can target 90% of the circulating virus but because this only happens 3 years after infection, this doesn’t help the person at all. We have had 6 HIV vaccine trials, none of which have done any better than 31% protection. The virus integrates into the person’s DNA, which makes a complete cure very difficult. We have cured one man by completely irradiating him twice and nearly killing him and we have thought we cured one baby by giving it ARVs in the first hours of its life (it has since rebounded), with little knowledge about how it will affect it over life. Please understand that the dearth of progress is not for lack of trying or because scientists are secretly plotting against adolescent women.

We simply have not figured it out yet.  Even with incredible education, support and dedication by some truly wonderful people in this country, there continues to be a barrage of infections. While social behaviours and injustices definitely help spread the disease, the ONLY thing that will stop it is a vaccine or a cure. It sounds noble to try and reinvent social interactions (a goal that must be pursued in our lifetime) but this is not what brings about a real-world cure to a horrible disease. Polio swept the world several times throughout history. Do you know when they stopped it? When they found a vaccine! (Read about other diseases defeated by vaccines here.)

The second thing that bothered me in Charlize’s talk, “I know this because AIDS does not discriminate on its own. It has no biological preference for black bodies, for women’s bodies, for gay bodies, for youth or for the poor. It doesn’t single out the vulnerable, the oppressed, or the abused.” This isn’t true: the disease does discriminate. Women are biologically more likely than men to contract the disease (read this link for an in-depth analysis and click here for a simplified version), and routes of transmission make gay men in particular vulnerable to infection. I understand what she is trying to say, but to a scientist these statements are incorrect and are once again, making the point that AIDS is only a social disease. People will never perceive themselves to be in a socially-constructed high-risk category. Many of the people I know own cars that they drive every day (a truly high-risk activity!) and not one of them wears a crash helmet.

Charlize later went on to say that we “have all the tools to end HIV.” And we don’t. The fact is education and empowerment doesn’t work completely. We need an intervention that people will not have to think about. How seriously do you worry about Pertussis every day or dying from Mumps? Everyone has access to these vaccines and that is what we need to do for AIDS. I agree completely with Baron Peter Piot (a researcher from the London School of Hygiene and Tropical Medicine) when he spoke at the same conference, “We need to stop saying that we have the tools to end the HIV and AIDs epidemic, until we have a cure or a vaccine- then we can say that.”

I wouldn’t want any young person to listen to Charlize Theron’s speech and assume that there is any lack of urgency in the scientific field because the disease is not prevalent in the white upper class. We are facing a terrible enemy and while we know a lot about it, it keeps coming up with clever ways to evade our advances. The world could always do with improvement. Young girls should think they are better than their relationships and can go on to live an HIV-free life. I applaud people trying to change this. Ultimately though, scientists are dedicated to making a vaccine for everyone. It, much like ARVs, will shape the lives of people much more quickly than changing social perceptions can. It would be easier if we could just give an injection that would bridge the social divide, but then again, I am a scientist looking out of scientist goggles, with potentially limited eyesight.

Posted on by ScientistSim

Exciting times for HIV vaccines, less exciting times for the virus

On International HIV Vaccine Awareness Day (the 18th May 2016) at the HIV Vaccine Trial Networks (HVTN) meeting, it was announced that for the first time in 7 years and the first time in Africa, a HIV phase 3 vaccine trial will be taking place. In addition to this the world’s first HIV antibody infusion trial started with its first South African participant in Soweto.

Slowly we seem to be completing a puzzle. Perhaps the most complicated one ever pieced together.

Science is a developing story. Every study, no matter how mundane, adds a puzzle piece to the picture. Sometimes it’s an edge piece, that forms the basis for studies to come and sometimes it’s a middle piece that doesn’t really help anyone at the time but will be imperative to complete the picture. In some cases though, in order to progress, scientists stop fitting in pieces to the main puzzle and start their own. This is a risk because the evidence is leading the field in a particular direction and this direction is fairly certain because multiple people have determined the same thing. Sometimes though, the risk of deviating is worth it. Risk shakes up the field; breaks down dogma and enforces flexibility. And that is what this trial could mean for HIV vaccinology.

I am beyond excited that we are having our first trial in seven years and I’m even more excited that it is happening in South Africa. Capacity building has happened over the last couple of years, allowing for South African clinicians and scientists to run these trials. This means much more opportunity for young scientists, collaborations, funding and all round focus. We are finally in the spotlight. The findings of trials always mean that interest in the field surges again. New ideas will be emerging from unexpected places.

The most recent vaccine trial regimen that showed any protection was the U.S. Military HIV Research Program-led RV144 clinical trial in Thailand completed in 2009. This regimen showed that protection was mediated by something we did not expect. All our data in the field up until that time suggested that antibodies (called broadly cross neutralizing antibodies) that could bind and coat lots of different HIV viruses (preventing entry into cells) would be our best shot at a vaccine. But protection (bear in mind it was only 31%) was achieved by antibodies that weren’t able to block infection of a cell. Instead they are able to bind to an already infected cell and call for backup. Other cells with the ability to secrete substances that pop the infected cell heed the call and come to destroy the infected. Think of the broadly cross-neutralizing antibody as Batman (pretty capable

robin batman 1
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of a fight on his own) and these other antibodies as Robin. The vaccine was tested in Thai people who have a very different epidemic to the part of the world that bears the greatest burden, Southern Africa. So the HVTN has run a series of small trials in South Africans using a vaccine that would be more appropriate for our situation. And now, we are paving the way to HVTN 702 (not to be confused with the talk radio station); the phase 3 trial guaranteed to rock the boat of science.

 

A phase 3 trial is a big deal. A wide range of criteria need to be fulfilled in order to proceed to one and the criteria that were set for HVTN 702 have all been met. However there is much talk in the field that we are progressing for progress’s sake. Many feel like we are creating a vaccine that has both arms tied behind its back and we are expecting it to win an arm wrestling contest. We are expecting robin to win Batman’s fight.  We are pushing a vaccine through that does not create the antibodies we know are going to protect people and are based on historically unimpressive antibodies. Should we be doing trials on things we know are not optimal or should we take the risk and acknowledge that there are clearly things we do not understand? Perhaps what now seems like an arbitrary puzzle piece will start off a new and exciting puzzle.

hero sidekick5400 South Africans will be enrolled from November 2016 and we will know the outcome by 2020. It’s a long time to spend on something that may not work again. What would going back to the drawing board mean for new infections? The bottom line is we have not yet managed to summon Batman to fight for our cause. We have lots of ideas on how to get him there but so far nothing has worked. Should we give up on Robin just because he is not what we expected?

Most vaccines have taken between 25-50 years to develop, so technically 30 years in, we aren’t doing too badly: we have drugs that are very effective at keeping AIDS patients well, which our government has now pledged to provide free of charge to everyone infected; we have drugs that can be used to prevent infection (pre-exposure prophylaxis) and we have lots of ideas bout what will protect people in a vaccine setting.

For me, the proof will be in the pudding. By 2020 we may have even brighter ideas about what we need and how to get there. And potentially the pessimistic view of the current phase 3 if irrelevant if it goes on to form new dogma. If all this phase 3 trial does is encourage bright and motivated young people to tackle arguably one of the most perplexing problems the world has, it will be a win. Either way, now is not a good time to be HIV.