The IAVI - leading the hunt for an AIDS vaccine
In the run up to World AIDS Day on 1 December, the World Health Organisation released figures showing that in 2007, 2.5 million people were newly infected with the human immunodeficiency virus (HIV). This works out at an average of over 6,800 new infections a day, and brings the total number of people living with HIV to 33.2 million. These statistics underline the importance of finding a vaccine against this devastating disease as soon as possible, and leading global efforts in this field is the International AIDS Vaccine Initiative (IAVI). When the IAVI was founded in 1996, there was very little AIDS vaccine research and most of this work was focused on developed countries. Over the years, the IAVI has striven to both significantly increase the amount of AIDS vaccine research going on around the world and shift the emphasis towards developing countries, where the majority of HIV positive people live. The fact that there are now around 30 candidate vaccines in clinical trials around the world is due in no small part to the work of the IAVI. 'We put AIDS vaccines back on the international agenda and vaccines back on the AIDS agenda,' said Frans van den Boom, Vice President IAVI, European Programmes. The organisation operates as a product development public private partnership (PDP), which unites industry, academia and government with the goal of speeding up the process of getting promising vaccine candidates from the lab and into clinical trials. An important facet of the organisation's work is capacity building for research in developing countries themselves. This includes building laboratories and clinics, and training local scientists and healthcare staff. The IAVI also collaborates with local institutions to reach out to communities via education and awareness-raising activities on clinical trials of candidate vaccines. When he spoke to CORDIS News, Dr Van den Boom had just returned from a trip to Rwanda, where the IAVI is working closely with Projet San Francisco. Over the last four years this project alone has provided advice on HIV prevention to some 30,000 couples. Without counselling, the HIV prevalence is this community is 25%; among the couples who have received counselling, it has fallen to just 3%. Part of this latter group will now go on to participate in trials of a potential HIV vaccine. The IAVI emphasises that all participants in its clinical trials receive extensive information both on the trial itself as well as actions they can take to reduce the risk of contracting HIV. They are also given access to other prevention methods such as condoms, and are free to leave the trial at any time. Developing a vaccine against a new disease is never easy; it took 47 years from the discovery of the polio virus to developing a polio vaccine. HIV was discovered just 24 years ago. However, developing an AIDS vaccine is proving particularly tricky. 'We are dealing with the most complicated virus that we know,' explained Dr Van den Boom. HIV mutates extremely fast, and there are many subtypes of the virus. Currently, scientists do not know whether a vaccine that is effective against one subtype will also be effective against other subtypes. Different subtypes prevail in different regions of the world. A second problem faced by vaccine researchers is the lack of a good animal model for HIV; this makes it hard to predict how a vaccine which appears to be effective in animals will work in humans. Finally, while many vaccines make use of a weakened version of the live virus, in the case of HIV this approach is considered to be too dangerous as such a vaccine could potentially cause the very infection it is meant to prevent. Instead researchers are forced to take alternative approaches which involve using only part of the HIV structure. These include proteins from the virus' outer shell, or copies of individual HIV genes. The problems involved in developing an effective vaccine were highlighted recently when a leading vaccine candidate, developed by Merck, proved to be ineffective in clinical trials. 'It was a disappointment for the field because it was thought it would be partially effective,' Dr Van den Boom told CORDIS News. However, the IAVI is keen to point out that although Merck's vaccine candidate failed, the trial did not. 'The contribution of the volunteers was not in vain,' said IAVI's President and CEO, Seth Berkley. 'As a result of their dedication, the field will have new data that will inform future vaccine design, help with the prioritisation of candidates in the pipeline and guide decisions on how to best proceed with ongoing and upcoming trials.' Ultimately, the IAVI remains optimistic that a vaccine against HIV will be found. 'We will continue to invest in research and also continue to move vaccine candidates into clinical trials,' Dr Van den Boom said. Solving the key scientific questions that hamper progress in AIDS vaccine development will be a major focus in the coming years. In light of this, the organisation recently expanded its infrastructure for applied science with an AIDS vaccine development laboratory, and set up an Innovation Fund, with the goal of stimulating innovation by bringing new players and fresh ideas into the field. The IAVI already receives grants from the EU to help it prepare communities for participation in clinical trials. However, according to Dr Van den Boom, the EU could do more. 'It is important for the EU to increase funding for AIDS vaccine research,' he said, pointing out that currently most money for AIDS vaccine research comes from the US. 'The second thing is that we don't have a good mechanism for translational research - how can we get promising candidates into the clinic as soon as possible? The mechanism to do this is urgently needed.'