VaxGen Unveils Details of Vaccine Trials, Says AIDSVAX May Be Ready Within Five YearsVaxGen, an American pharmaceutical company, yesterday told attendees at the XIV International AIDS Conference in Barcelona, Spain, that it expects its AIDS vaccine candidate AIDSVAX to be available within the next five years, half a decade earlier than initially predicted, BBC News reports (BBC News, 7/8). The vaccine candidate, which uses genetically engineered proteins -- not HIV itself -- to stimulate an immune response to the virus, is currently in late-stage human testing involving 8,000 people in Thailand, the United States, Canada, Puerto Rico and the Netherlands, and preliminary results are expected by the spring of next year (Guardian, 7/8). AIDSVAX is also scheduled to begin testing later this year in 16,000 people in Thailand in conjunction with ALVAC, a separate vaccine candidate that uses a canarypox virus carrying specific HIV genes to elicit a different kind of immune response. Half of the study participants will receive four injections of the two vaccine candidates over a six-month study period, while the remaining participants will receive placebo injections (Washington Times, 7/9). VaxGen chief Don Francis said he is optimistic that AIDSVAX will be effective both in tandem and on its own. "I think we will get protection [from HIV with just AIDSVAX], but I don't know what level we'll get," he said (BBC News, 7/8). Any vaccine candidate will have to be proven to be effective in at least 33% of people who receive it in order to gain approval.
Observers cautioned that it is too early to determine whether AIDSVAX, or any of the other seven vaccine candidates in the human-testing phase, will ultimately be effective in protecting against HIV/AIDS. "It is a bit premature for the company to say that it expects it to be effective. We have to be very cautious," Jose Esparza, coordinator of UNAIDS' HIV vaccine initiative, said. However, he commended VaxGen for its "commitment" to AIDS vaccine research, saying, "Unless we go through these difficult trials we will never have a vaccine, and the company needs a lot of support" (Guardian, 7/8). Marty Algaze of Gay Men's Health Crisis said his group thinks AIDSVAX has "little hope of showing effectiveness" in its current Phase III trials because early results were "disappointing." He added that VaxGen is "'hyping' the vaccine's potential" (Ferraro, New York Daily News, 7/9). Seth Berkley, president of the International AIDS Vaccine Initiative, noted that even if the vaccine is proven effective in the next few years, it may take up to half a decade or more before it can be manufactured on a large scale and distributed in the worst-affected areas. "The critical issue is, if a vaccine turns out to look good but we don't have the manufacturing facilities, the delivery systems or the financing systems, what will happen is that we'll have 'Eureka! This great advance,' but we won't be able to use it for a very long time," he said, adding, "If you wait until the day we have a vaccine that works, it'll be five or more years before it gets to the places that need it" (Reuters Health, 7/8). Berkley noted that an effective vaccine would initially be targeted at "high-risk" groups such as injection drug users and sex workers until larger amounts of the vaccine became more widely available (BBC News, 7/8).
PRI's "The World" yesterday reported on the VaxGen announcement. The full segment is available in RealPlayer Audio online (Bell, "The World," PRI, 7/8).
California Company to Collaborate With South African University on AIDS Vaccine
In other vaccine news, California-based Large Scale Biology Corp. yesterday signed an agreement with the Institute of Infectious Disease and Molecular Medicine at the University of Cape Town in South Africa to collaborate on the development of an AIDS vaccine, the Owensboro Messenger-Inquirer reports. The vaccine, which may be designed to treat as well as prevent AIDS, will be produced at Large Scale's plant in Owensboro, Ky., and will undergo testing in South Africa under the university's guidance. Under the agreement, Large Scale retains the rights to sell and market any vaccine in North America and Europe, and the university would hold the rights to sell the vaccine in Africa. Rights would be shared in other regions. The two groups did not announce a specific timetable for vaccine development, but said they would like to have an "affordable, effective and locally relevant HIV vaccine" by 2010 (Lawrence, Owensboro Messenger-Inquirer, 7/9).