The Population Council announced that the Phase 3 clinical trial of the Council’s candidate microbicide Carraguard® found the product to be safe for vaginal use. The trial did not demonstrate that Carraguard is effective in preventing male-to-female HIV transmission during vaginal intercourse.

There were 134 new infections in the Carraguard group (an incidence of 3.3 infections per 100 woman-years) and 151 new infections in a placebo group (an incidence of 3.7 per 100 woman-years). The difference between the two groups is not statistically significant.

Carraguard is the first product developed as a microbicide to complete the final phase of product testing. “We are disappointed that this trial did not show Carraguard to be effective; nonetheless the completion of this trial is a milestone in HIV prevention research,” said Population Council president Peter Donaldson. “The trial has contributed significantly to the field’s body of knowledge regarding product development, trial design, and women’s and their partners’ willingness to use a vaginal gel consistently. The data from the trial will be used by the Population Council and others working on microbicides to improve future products and trials.”

The trial was funded by the US Agency for International Development (USAID) and the Bill & Melinda Gates Foundation. Jeff Spieler, senior science advisor in population and reproductive health at USAID, said, “We have always known that the path to developing a successful microbicide would be a long one. The Population Council has done groundbreaking work in completing this trial, even though we are terribly disappointed that the product was not shown to be effective. Now we all have to redouble our efforts to develop a microbicide that women can use to protect themselves.”

The full text of the announcement and more information about the Population Council’s microbicides program is available at:

www.popcouncil.org/microbicides/Resources.html.