Gilead’s daily HIV prevention drug called Truvada, is not working, so studies have been stopped for now. In particular, women taking it are just as likely to get HIV as other women who have been given placebos. Even if the study were to continue, it would not be able to determine whether the pills help prevent infection, researches said.
Family Health International (FHI), a nonprofit organization involved in AIDS research, announced the new results on Monday. The group launched the study two years ago and had enrolled about half of the 3,900 women intended in Kenya, Tanzania and South Africa. As of last week, 56 new HIV infections had occurred, half in each group.
The FHI outcome is surprising and disappointing, given a number of earlier studies suggesting the promise of pre-exposure prophylaxis (PrEP) using antiretrovirals. Most recently, the iPrEX study showed that use of Truvada can prevent infection in men who have sex with men at risk of HIV.
There are a number of possible reasons for the study findings, including low adherence to study regimen, a true lack of effect of the product among women (versus men who have sex with men), or other factors still to be determined. FHI will be conducting further analyses and will share additional findings in the coming months. The IDMC commended the trial team on a study conducted to a high standard with good follow-up and careful attention to good clinical practice and ethical standards.
The organization stated:
“FHI and its partners are especially grateful to the women whose willingness to participate and commitment to the study were essential. To the extent possible, all participants have been notified of the decision and are being asked to come to the study clinics for final visits. Study participants who became infected with HIV during the study are being followed by the study team for an additional year and are referred for appropriate medical care and treatment in their community.”
The finding is also disappointing because another study last fall concluded that Truvada did help prevent infections in gay and bisexual men when given with condoms, counseling and other prevention services. Many AIDS experts view that as a breakthrough that might help slow the epidemic.
No safety problems were seen with Truvada. However, women taking it were more likely to become pregnant than those on dummy pills.
Two other large studies testing AIDS drugs for prevention are under way in Africa, in heterosexual women and in couples where one has the virus and the other does not. Results are expected within two years. The studies have mostly been in countries with high rates of new infections because that makes it easier to see whether a prevention measure is having an impact.
Truvada costs $5,000 to $14,000 a year in the United States, but as little as $140 a year in some poor countries where it’s available in generic form.
The FHI finalizes their official statement by concluding:
“When available, the final results from FEM-PrEP will make a strong contribution to our understanding of the use of antiretrovirals for HIV prevention. FHI, USAID, and research partners in Africa are committed to finding new technologies and developing new strategies to protect women from HIV.”
Sources: Family Health International and
Written by Sy Kraft