Global HIV/AIDS Vaccine Conference in South Africa To Seek New Strategies Against Disease
Experts at a four-day global HIV/AIDS vaccine conference in Cape Town, South Africa, that opened Monday plan to seek "fresh strategies" against the disease, with experts "weighing the value of basic laboratory research against large-scale human clinical trials after a string of disappointments," Reuters reports. According to experts, approaches focusing on "neutralizing antibodies" that would allow the human immune system to block infection completely are likely to become the focus over existing models that seek to manage HIV after infection with the virus.
Lynn Morris, co-chair of the AIDS Vaccine 2008 conference and head of the AIDS unit at South Africa's National Institute for Communicable Diseases, said, "There's a real redirection and rethinking," adding, "Fundamentally, we don't understand enough about the human immune system, and we don't know how the immune system deals with HIV."
Reuters reports that the conference follows a year of several setbacks in HIV vaccine research (Quinn, Reuters, 10/12). Merck in September 2007 announced it had halted a large-scale clinical trial of its experimental HIV vaccine after the drug failed to prevent HIV infection in participants or prove effective in delaying the virus' progression to AIDS. The vaccine candidate also might have put some trial participants at an increased risk of HIV. Following news of the Merck vaccine, trials of NIH's Vaccine Research Center's HIV vaccine candidate were scaled back (Kaiser Daily HIV/AIDS Report, 3/25).
As a result of the setbacks, Morris said research now will focus on laboratory work to discover how to help the body produce antibodies to prevent infection altogether. "Neutralizing antibodies are a major component of almost all other vaccines," Morris said, adding, "I think there is going to be a real swing back to thinking about them."
However, Reuters reports that "renewed focus on lab work has left some scientists and advocates worried that human clinical trials of vaccine candidates may suffer as funding shifts toward basic research." Nevertheless, Morris said that limited human trials of new vaccine candidates would have to continue, arguing against some researchers who say funding should go to animal research or improved antiretroviral drugs. "There's no guarantee that basic researchers are going to come up with the answers," Morris said, adding, "But I feel quite strongly that clinical research should continue. If people are willing to participate in this because there is a hope that we may develop a vaccine, then that's what I think we should be doing." In terms of the recent disappointments in vaccine research, Morris said they should not affect the pace of research. "It's an iterative process," she said, adding, "You don't just boom, come up with a vaccine. We have to accept that maybe it's not going to be possible. But until we know that, we have to keep trying" (Reuters, 10/12).