NEW YORK, April 18, 2011 - Sponsors of the pre-exposure prophylaxis (PrEP) clinical trial FEM-PrEP announced today that following a scheduled interim review of study data, the Independent Data Monitoring Committee advised that the trial will be highly unlikely to determine that the study drug regimen decreased risk of HIV infection among HIV-negative women at risk via sexual transmission. As a result, the trialâ€™s sponsors have decided to initiate an orderly closure of the study over coming months. Investigators plan to conduct further analyses to examine the possible reasons for the studyâ€™s findings.
The FEM-PrEP trial, implemented by a partnership between the global health and development organization FHI and several research centers in Africa, to date has enrolled nearly 2,000 female volunteers in Kenya, South Africa and Tanzania. It aims to test the effectiveness of a daily dose of the antiretroviral drug Truvada (a combination of tenofovir and emtricitabine) in preventing HIV infection among the study population of HIV-uninfected women.
Although the news of this trial's planned closure is disappointing, the International AIDS Vaccine Initiative (IAVI) stresses that scientists and activists in the field of HIV prevention should not be discouraged. In recent months the field has seen promising results from several studies, including the iPrEx PrEP trial, which indicated that a daily regimen of Truvada was able to reduce HIV acquisition among the trial population of men and transgender women who have sex with men, and the CAPRISA 004 microbicide trial, which showed a reduced risk of HIV acquisition among women who used a tenofovir vaginal gel. Devising new tools for the prevention of HIV has proved to be a long-term endeavor, and the community is likely to face many hurdles along the way to licensing new tools to prevent HIV infection.
Despite the setbacks we in the HIV-prevention field have faced, the knowledge gleaned from clinical trials such as FEM-PrEP has consistently advanced our understanding of HIV prevention and provided guidance for future trials. This knowledge could help scientists improve upon other candidate prevention tools and will help to determine which candidates are most likely to work.
IAVI CEO Seth Berkley noted that the field of HIV-prevention research owes a debt of gratitude to the volunteers who have participated in the FEM-PrEP trial, as well as to the sponsors of the study. Berkley stated, "In recent years we've seen an abundance of progress and promise in development of new HIV-prevention tools, but we must remember this virus is an extremely tough adversary. That means it is imperative - now more than ever - that progress not slow in the face of challenges. Developing effective prevention tools for HIV is the medical and scientific challenge of our time and will require resilience and sustained commitment."