Volunteers are randomised into groups, which will receive various combinations of the two vaccine components or a placebo at differing intervals. This is predominantly a safety study but the information collected may help establish optimum dosage, how many booster injections to give and a vaccination schedule. All of this information will contribute to the eventual evaluation of the vaccine's effectiveness.
Professor Jonathan Weber of Imperial College of Science, Technology and Medicine is leading the team that will co-ordinate the London end of the trial, from St Mary's Hospital, Paddington. They will collaborate with colleagues led by Professor Andrew McMichael, honorary director of the Medical Research Council Human Immunology Unit in Oxford, (MRC HIU). The teams need to recruit 120 volunteers in total from the London and Oxford regions. They must be between the ages of 18 and 60, HIV negative and at low risk of HIV infection and able to attend 12 appointments over the course of a year.
The International Aids Vaccine Initiative (IAVI) is funding the trial. This research is part of the larger initiative to develop a simple, effective and affordable HIV vaccine, which is the basis of the unparalleled partnership between IAVI, the MRC HIU and the University of Nairobi, Kenya. Imperial College will play an important role in this phase of the UK trials.
The vaccine has two parts, one to prime the immune system and one to boost it. The DNA (prime) component contains genetic information about the virus to prime the immune system and provoke an immune response. The body is tricked into defending itself against the virus before it is there. The aim is to give the body a head start in fending the virus off to stop it overpowering the immune system and taking hold. An MVA (modified vaccinia ankara) booster, which contains the same genetic information and has a powerful ability to stimulate the killer T-cells, is used to keep the immune system responding.
Genetic information about the Clade A HIV-1 virus, one of the commonest strains in Eastern Africa, is contained within the vaccine. There is no live HIV material so participants are not at risk of infection.
Professor Jonathan Weber said: "Timing and dosage of vaccines is crucial to the overall success of a trial such as this. It will help establish whether the vaccine works and what procedures should be in place for healthcare programmes. I'm sure the people of London will respond to our need for volunteers - it's a chance to help us save lives."
Professor Andrew McMichael said: "We're pleased with the progress we are making with the trials, but there's still a lot of work to do. There's a strong sense of joint purpose between the team in Oxford, colleagues at the University of Nairobi and International Aids Vaccine Initiative (IAVI) about what we're trying to achieve. It's great to have the expertise of the London team on board as well."
Seth Berkley, President and Chief Executive of IAVI said: "These trials are a significant step in IAVI's objective to fast-track a diverse portfolio of AIDS vaccines in human testing. We raise a hand to salute progress on the vaccines being tested in Oxford and London, while moving forward on other fronts to meet the research challenges yet remaining."
Extensive studies of sex workers in Nairobi and elsewhere gave the clues that helped in the design of the vaccine. Despite frequent exposure to HIV, a small minority of these women has resisted infection over many years.
Professor J. J. Bwayo, who is chairman of the Department of Medical Microbiology at the University of Nairobi and Principal Investigator of the Trial said: "These women make an immune response which the vaccine is trying to emulate. Further trials will help us determine if the vaccine can stimulate the same strong cellular immune response to HIV that we have seen in these women."
The start of the trial was also welcomed by Derek Bodell, Chief Executive of the National Aids Trust who said: "The trial is an important step towards the development of a safe and effective HIV vaccine. NAT particularly welcomes the development of vaccines specifically designed for use in Africa. NAT believes that UK vaccine development should prioritise vaccines that will work to combat HIV in highly affected countries. Globally we need to strengthen prevention education efforts while at the same time giving priority to developing new prevention tools such as vaccines."
Anyone in London or Oxford who is eligible and interested in joining the trial can call:
London: Ken Legg, Miranda Cowen or Dr Nicky Mackie on 0800 587 4406
Oxford: Mary Brooks or Dr Inese Cebere on 0800 169 6978
For more information and to interview Professor Weber, or other members of his team, please call Imperial College press office - Tom Miller 020 7594 6704.
For more information or to interview Professor McMichael or the Oxford team, please call MRC press office - Dawn Duncan 020 7637 6011
For more information or to interview Dr Berkley please call the IAVI press office - Christopher Adasiewicz - 001 212 847 1049
For more information or advice about HIV and AIDS related topics or to interview Derek Bodell, you can contact the National Aids Trust press office - Suzanne Williams - 020 7814 6730
Notes to editors
1. An estimated 5 million people worldwide were infected with HIV last year.
2. The Imperial team have started recruiting and screening volunteers but need as many people as possible to come forward to find the correct number of eligible participants. Volunteers are also needed by the MRC team in Oxford where enrolment should begin shortly. Potential volunteers will be fully briefed and informed through both written material and seminars before being asked to make a commitment to taking part. They will be asked to do so only on the basis that they their consent is fully "informed", In addition, they will be free to withdraw from the study at any time.
3.The vaccine is designed in the hope it can beat HIV in places where it is needed most urgently. The Clade A HIV-1 virus is one of the commonest in Africa and affects two-thirds of the HIV+ Kenyans.
4. Killer T-cells are cells which can attack and destroy other, infected cells in the body.
5. A modified vaccinia ankara is a weakened pox virus, which is used to carry the genetic information of the HIV-1 Clade A virus. This is the first time an MVA approach is being used in a trial of an HIV vaccine.
6. The inspiration for the approach to the vaccine was the seeming natural immunity to the HIV virus witnessed in prostitutes in the Nairobi slums. Researchers have designed a vaccine to simulate the natural immune response of these women.
7. The vaccine trial was launched in Oxford, August 2000 http://www.mrc.ac.uk/index/public_interest/public-press_office/public-press_releases_2000/public-mrc-48-00.htm when Dr Evan Harris, MP became the first volunteer to receive an injection. At the University of Nairobi in Kenya the first trial and they started in March 2001 and are be led by Dr J J Bwayo at the Department of Medical Microbiology and his team. If these stages are successful, larger Phase 3 trials will be conducted at a later date.
8. DNA vaccines are a new way to tackle the problem of priming the body to fight disease, using only small parts of a virus' information carrying system (DNA). By prompting a few key cells in the body to make fragments of some of the virus proteins, they stimulate a strong immune reaction without running any risk of actually causing the disease. In HIV infection the virus renders the immune system so weak it can not fight back quickly enough and is overpowered. However if the immune system is already primed by vaccination there is a good chance that the body could fight HIV effectively and stop it taking hold. An AIDS vaccine is believed to offer the best hope for preventing the spread of HIV. DNA and MVA are two promising designs
9. Imperial College of Science, Technology and Medicine is the largest applied science, technology and medicine university institution in the UK. It is consistently rated in the top three UK university institutions for research quality, with one of the largest annual turnovers (£390 million for 2000-01) and research incomes (£202 million for 2000-01). In the December 2001 Research Assessment Exercise, 75 per cent of staff achieved a 5* rating, the highest proportion in any UK university. All departments visited and assessed for their teaching have scored between 21 and 24 points out of 24 or, in the previous system, have been judged excellent. Web site: www.ic.ac.uk
10. The Medical Research Council (MRC) is a national organisation funded by the UK tax-payer. Its business is medical research aimed at improving human health; everyone stands to benefit from the outputs. The research it supports and the scientists it trains meet the needs of the health services, the pharmaceutical and other health-related industries and the academic world. MRC has funded work which has led to some of the most significant discoveries and achievements in medicine in the UK. About half of the MRC's expenditure of over £367 million is invested in its 50 Institutes, Units and Centres, where it employs its own research staff. The remaining half goes in the form of grant support and training awards to individuals and teams in universities and medical schools. Web site at: www.mrc.ac.uk
11. The International AIDS Vaccine Initiative (IAVI; www.iavi.org) is a global nonprofit scientific organization working to speed the search for vaccines to prevent HIV and AIDS and help guarantee that future vaccines will be rapidly available to all. IAVI's focus is AIDS vaccines for developing countries, where 95 per cent of the nearly 15,000 new HIV infections daily are occurring. IAVI's major financial supporters include the Bill & Melinda Gates Foundation; the Starr, Rockefeller and Sloan foundations; the World Bank, BD (Becton, Dickinson and Company); and the governments of the Netherlands, United Kingdom, United States, Canada, Ireland, Denmark and Norway. IAVI was founded in 1996 and is a collaborating centre of the Joint United Nations Programme on HIV/AIDS (UNAIDS). 12. NAT is the UK's leading policy development and advocacy organisation working to ensure that people in power take action on HIV both within the UK and internationally. NAT is the UK partner in the International AIDS Vaccine Initiative.