The US FDA has strongly backed approval of the first-ever drug for the prevention of sexually acquired HIV-1 infection. The panel recommended approval of a supplemental indication for Truvada (emtricitabine/tenofovir disoproxil fumarate) for preexposure prophylaxis (PrEP) in:
- HIV-uninfected men who have sex with men,
- HIV-uninfected partners in serodiscordant couples, and
- Other individuals (such as sex workers) who are at risk of acquiring HIV through sexual activity.
However, there is concern that healthy people taking Truvada for HIV prevention will be harmed if they become infected with HIV and do not change from single-drug PrEP prophylaxis to a 3-drug combination antiretroviral treatment regimen, that continuing single-drug Truvada after HIV infection will lead to development of Truvada-resistant viral strains, and that taking the PrEP regimen increases the risk for adverse effects, particularly kidney damage.
Men who have sex with men (MSM) represent 2% of the population older than 13 years and account for from 56% to 61% of new HIV infections annually.
Data from the Preexposure Prophylaxis Initiative (iPrEx) trial found that MSM participants who took Truvada daily had a 44% reduction in HIV incidence over the course of 1.2 years of follow-up compared with placebo. Results of the iPrEx study were published online November 23, 2010, in the New England Journal of Medicine.
Truvada is already being seen as a “medical condom” (in the words of AIDS Healthcare Foundation’s Whitney Engeran-Cordova) and might be taken intermittently or as a “party drug,” leading to rapid development of Truvada-resistant HIV.