Clinical trial of new HIV vaccine
Saturday, September 26, 2009. A clinical trial of a new HIV vaccine has proved effective in cutting the infection rate of the virus that leads to Aids.
The US Army carried out tests on 16,000 HIV-negative volunteers in Thailand.
It found that infections were prevented in over a third of the 8,000 people who received the vaccine, compared with the other 8,000 who were given the placebo.
The study, which started in 2003, used a combination of two vaccines, both of which have proved to have little or no effect on infection rates when used as single doses in previous trials.
In the final analysis, 74 placebo recipients became infected with HIV compared to 51 in the vaccine regimen group.
Although a difference of 23 people is not huge, the 31.2% decrease has given scientists hope that in the future there could be a way of preventing the spread of this highly contagious virus which infects around 6,800 people a day.
Lieutenant General Eric Schoomaker, Surgeon General, US Army said: 'We are very excited and pleased with the outcome of this trial and congratulate all those who participated in it.'
The purpose of the study was to evaluate how well the vaccine could prevent infection as well as reduce the amount of HIV in the blood of someone who has already tested positive.
The research found the vaccine had no effect on the amount of virus in the blood of volunteers who became HIV-infected during the study.
Although the findings show potential for a successful vaccine in the future, scientists say more research needs to be done into how this particular vaccine reduced the risk of infection.
Sky News health correspondent Thomas Moore said: 'This is the first time we have seen such a big effect from an Aids vaccine trial.'
But he added that the results 'were not significant enough for you to be confident relying on this vaccine to protect yourself from a deadly disease'.
There is currently no cure for Aids but anti-retroviral drugs can be taken to limit the symptoms.
Colonel Nelson Michael, Director, Division of Retrovirology, Walter Reed Army Institute of Research and Director, US Military HIV Research Program (MHRP) said: 'These results show that development of a safe and effective preventive HIV vaccine is possible.'
More detailed results of this study will be presented next month at the Aids Vaccine Conference in Paris, France.
