Oral PrEP is a critically important HIV prevention tool that can play a significant role in reducing individual infection risk and helping to end the epidemic. Today's news, that PrEP prevents HIV among people whose primary infection risk is injection drug use, adds to clear evidence from earlier studies that PrEP is safe and effective at preventing the sexual transmission of HIV in gay and bisexual men and in heterosexual women and men. With this new evidence we now know that PrEP, which was FDA-approved to prevent sexual transmission of HIV in 2012, can help HIV-uninfected people protect themselves from HIV regardless of the route of exposure.
The CDC's Bangkok Tenofovir Study confirmed the lessons of other PrEP studies:
- PrEP is effective: In intention to treat analyses across these studies, PrEP reduced new HIV infections by up to 73%.
- Consistent use of PrEP increases its effectiveness: In this study and others, more consistent use of PrEP resulted in greater protection from HIV infection. In iPrEx and other studies, daily use of PrEP reduced HIV infections by an estimated 90-100%.
- PrEP is safe: This PrEP study, the longest ever conducted, involving up to 6 years of PrEP exposure, confirms the safety findings of previous studies, with no significant side effects associated with PrEP.
- PrEP is versatile. With this study, PrEP has now been shown to be safe and effective at reducing HIV exposure through vaginal sex, anal sex and injection drug use.
Access to clean needles remains critical in the fight against HIV transmission through injection drug use, which is a major contributor to the epidemic in much of the world. We remain focused on strengthening global efforts to ensure broad access to every proven HIV prevention tool, including access to clean needles and PrEP.
The iPrEx team congratulates the volunteers, staff and sponsors of this important study. We must now move quickly to implement projects that will demonstrate the most effective way to use PrEP among people at risk for HIV through injection drug use, and to step up efforts to make PrEP broadly available for the other populations, including gay and bisexual men and heterosexual women and men. With 2.5 million new HIV infections occurring last year alone, there is no reason to delay efforts to make PrEP available to the millions of people worldwide who new, safe and effective HIV prevention tools.
Robert Grant, M.D., M.P.H., of the Gladstone Institutes and the University of California at San Francisco, is the iPrEx protocol chair.