The decision to stop clinical trials on nearly 1,500 volunteers deals a serious blow to research in this field. 24 of the 741 people in the group who had received the experimental vaccine were infected with HIV (versus 21 out of 762 for the group that received a placebo). All the volunteers were initially HIV-negative but more exposed than the average population to the risk of infection.
Two and a half years of work. Started in December 2004, the trial focused primarily on male homosexuals and prostitutes. Since February, the V520 test had been taken up a notch, with a trial on more than 700 uninfected people in five South African hospitals. Such a large-scale project had never been conducted in Africa, particularly in South Africa where 5.5 million HIV-positive individuals are struggling to survive.
A promising project.
Indeed, unlike first-generation experimental vaccines that sought to direct the body’s immune system towards HIV, V520 focused on another weapon of the human immune system: T lymphocytes. These killer cells, specialized in antiviral defense, were the target of this experimental vaccine. The AIDS virus has caused over 25 million deaths in the past 25 years.
