CDC: PrEP option for injection drug users

The Centers for Disease Control and Prevention (CDC) recommended preexposure prophylaxis (PrEP) to injection drug users who are at high risk of HIV infection, following the positive results of the Bangkok Tenofovir Study, published online June 12 in the Lancet.

In this phase 3 randomized, double-blind, placebo-controlled trial, more than 2,400 adults between 20 and 60 years old were randomized to receive either daily oral tenofovir disoproxil fumarate at a dose of 300 mg or placebo. At monthly follow-up visits, participants were counseled on medication adherence and HIV risk reduction, tested for HIV and in women, also for pregnancy, and assessed for adverse effects. Study clinics also provided primary medical care, social services, methadone, condoms, and bleach for cleaning injection equipment.

The study began in 2005 and continued through 2012. During a mean follow-up time of 4.6 years, almost one-quarter of the tenofovir-treated group was lost to follow-up or withdrew and 23% in the placebo group. Participants had an average adherence rate to tenofovir of 83.9% of the days and the majority received directly observed therapy.

During the trial, 50 patients tested positive for HIV infection, and of these, 17 were in the tenofovir group and 33 in the placebo group. HIV incidence was significantly reduced in the tenofovir group compared with the placebo group (48.9%); HIV incidence was 0.35 per 100 person-years in the tenofovir group and 0.68 per 100 person-years in the placebo group.

In addition, risk behaviors in both groups over 12 months of follow-up declined significantly for injecting drugs, sharing needles, and having multiple sex partners. Participants’ behaviors continued below the baseline throughout the study.

In July 2012, FDA approved the use of fixed dose combination of tenofovir (300 mg) and emtricitabine (200 mg) (Truvada) as PrEP for the prevention of sexually transmitted HIV by men who have sex with men and by heterosexual women and men.

As an update to its interim guidance for PrEP for HIV prevention, CDC recommended PrEP with daily Truvada for injecting drug users.

“CDC recommends that prevention services provided for [injecting drug users] receiving PrEP include those targeting both injection and sexual behaviors,” according to the Morbidity and Mortality Weekly Report, published June 14.