I thank the committee for the invitation. I will give an update on the field of AIDS vaccination and our programme in particular in the context of the overall fight against HIV/AIDS.
I will start with the results of the Thai trial, because they are significant, and by explaining what types of vaccine are not being tested against HIV. The most effective vaccines we know — against diseases for which we currently have vaccines — are live attenuated vaccines, in which the virus is attenuated and delivered to people, and whole killed virus vaccines. These two approaches are not used for HIV because there is anxiety that the live attenuated virus will mutate into wild virus and infect people rather than protecting them. The approaches we have used so far are state of the art, scientifically speaking, but are not considered to be as effective as the live-attenuated and whole-killed approaches.
Before the Thai results we had a number of solid reasons to believe a vaccine was possible. First, with a live attenuated vaccine we can protect monkeys completely against SIV, a sister virus to HIV. People who become infected with initial high viral loads are able to bring down those viral loads and remain without symptoms for several years. There are a number of people in whom infection is controlled without treatment — the so-called long-term non-progressors — and there is a subset of people who are frequently exposed to HIV but do not get infected. Those were the indicators that an AIDS vaccine would be possible. The significance of the Thai results is that now we have proven that a vaccine — in this case, a combination vaccine — can protect people. It is 30% efficacious. Most likely, that is not enough to license it in Thailand. Additional studies will be done in the next couple of months but this was a very important result because it provides clues as to the mechanism of protection, to what differentiates the placebo group who became infected from the vaccinated group who became infected and what differentiates those who became infected from those who remained unaffected.
It will give us additional information on the immunological response needed as well as information to validate the animal models we have been using so far. One of the problems with HIV vaccine research has been that what works in mice does not necessarily work in monkeys and what works in monkeys does not necessarily work in humans. For many other vaccines there is a valid animal model and, therefore, what is tested in animals is a fairly good predictor as to whether it would work in humans who do not have HIV. That is the significance of the Thai trial.
The significance of the neutralising antibodies identified is that they are the two most potent broadly neutralising antibodies we have seen and identified since the identification of HIV. Only four broadly neutralising antibodies had been identified. These are two new ones and there will be more. I shall provide an update on the neutralising antibody consortium and how that came about but the two in question are broadly neutralising and, most important, are easily accessible. The other ones were captured by very complicated glucose structures which were very difficult to attach to the epitobe. In this case, it is a great deal easier to attach to the virus and that is an important finding.
The third important finding to be presented at the PERC conference today, or perhaps yesterday, is that if one takes replicating factors it is possible to protect non-human primates against HIV infection. There is much interesting and important news in the AIDS vaccine field. We can speak now of a sort of renaissance in vaccine research and development. In the past couple of years we have seen a number of disappointments but this year there has been much progress and investments are really starting to pay off.
Considering the broader picture, why do we need an AIDS vaccine? The broader picture, of course, is that for every two people who are put on treatment in developing countries there are five new infections. If we want to put an end to the epidemic of HIV we need to develop more effective tools than those we have used so far. Behavioural interventions are important, as is arms reduction but the course of the epidemic has shown that behavioural interventions alone are not enough to stop the course of the epidemic. Although at a global level people say that HIV is stabilising, in sub-Saharan Africa HIV is very much a generalised epidemic with a large number of infections still ongoing. Vaccination programmes come in addition to the rolling out of preventive interventions and treatment programmes. We must bring an end to, or lower, the incidence of new cases of HIV. UNAIDS has done some modelling studies on the cost of HIV in 2015 that show the cost of universal access would be approximately $150 million on an annual basis, which is not sustainable. As Michel Sidibé, the executive director of UNAIDS, said recently, we cannot be kept hostage by treatment. We realise we have to put people on treatment but if we do not stop infection and are not more effective in prevention we will never be able to reach the goal of universal access.
What distinguishes IAVI from other organisations that work on AIDS vaccines? First, we are the only organisation worldwide that focuses on AIDS vaccine development. Many organisations work on AIDS vaccines but they also work on other diseases. Second, since the beginning of the organisation, we have involved the countries in the south in the research and development process. When we started in 2001 many scientists said IAVI's approach was stupid, that it was not possible to do early-phase trials in developing countries. Neither the expertise nor the infrastructure was to be found and therefore it was much easier to do the work in Europe, the United States, Japan or Australia. When one wanted to do efficacy trials one could go then to the developing countries and do a large-scale trial. We said that was not a correct model that we felt we had to work in and with the developing countries from the very start. Deputy O'Hanlon was one of the Members of Parliament who visited the trial sites in Uganda and Kenya. We built first-class trial and laboratory capacity in one of the laboratories in Uganda which is now one of the six global reference laboratories. For us, it proved that if there is commitment and a will to build such capacity, it can be done. In total, approximately 700 local staff are employed working on AIDS vaccines in the developing world.
In those clinical research centres we have taken seven different vaccine candidates into clinical trials in the past couple of years. That is an achievement in itself. Nobody else in the field has been able to implement that kind of portfolio approach to AIDS vaccine development. We have built large cohorts in order to get a good idea of the epidemiology and the normal reference values in the populations of developing countries. One of the studies was what we call Protocol G. That protocol is implemented in 21 countries worldwide, most of them in the south. It focused on people who are called "elite controllers". They are infected but show no symptoms. It was in that population that we identified the two broadly neutralising antibodies. They come from one person living with HIV. The expectation is that in the next couple of months we will identify more broadly neutralising antibodies. The relevance of that protocol is that it was primarily implemented in the south, whereas most of the other studies are taking place in the north. One likes to have broadly neutralising antibodies that are genetically close to the kind of sub-type prevalent in a given country. This is a prime example of how developing and developed countries can work together in order to isolate and identify broadly neutralising antibodies. Ultimately, these are the kinds of efforts that are needed to get a vaccine to the populations that need them most.
The last thing I would like to mention is the IAVI model. We were the first public private partnership in global health. The rationale for that was very simple. HIV is a very complicated and complex virus and there is a huge need for a vaccine in developing countries. However, in those countries there is no market and no money. Therefore, if one combines a very complex scientific problem and no market there is very little incentive for the pharmaceutical industry.
There is a good deal of work going on in academia and some work going on in biotechnology and big pharma. We must identify the most promising leads, whether from academia, biotechnology or big pharma, and move forward those promising initiatives. That is what we have done in the past and what we continue to do and what we will continue to do in the future.
As the Chair indicated, Ireland has been a leader in supporting AIDS vaccine research and development, especially in its support of IAVI, the International AIDS Vaccine Initiative. As the Committee is aware, given the economic recession Ireland had to interrupt its support for IAVI for 2010. However, we hope the economic situation will improve quickly. We are confident and hopeful that once the economic situation improves Ireland will continue to support AIDS vaccine development because, ultimately, when it comes to HIV and AIDS we must think through the endgame. At this point many people are focussed on the short-term needs, including the distribution of treatment and prevention. However, if we do not focus on the end game we will never win the fight against this epidemic.
