Author Interviews, HIV, NEJM, Sexual Health / 02.12.2015
Sexual Activity Based Antiretrovirals Reduce HIV in MSM
MedicalResearch.com Interview with:
Dr Jean-Michel Molina
Department of Infectious Diseases
Saint-Louis Hospital and University of Paris Diderot
Paris France
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Molina: Men who have sex with men (MSM) are disproportionately affected by HIV worldwide and represent the today in Europe the largest group in which new HIV infections are diagnosed with no decrease over the last 8 years.
The first study assessing preexposure prophylaxis (PrEP) efficacy among MSM was published in 2010 (the Iprex study) which reported for the first time a 44% reduced incidence of HIV in those randomized to receive daily tenofovir/emtricitabine TDF/FTC (one pill per day) as compared to placebo. Adherence to a daily pill regimen was found to be challenging however since only half of the participants (according to drug detection in blood) were taking their daily regimen. Post-hoc analyses suggested that among those with drugs detectable in plasma, PrEP efficacy could be as high as 92%. However, long term adherence to a daily regimen represents the Achille’s heel of daily PrEP, as shown later in other large PrEP trials among women in Africa (VOICE and Fem-PrEP).
Based on data from animal models we wished to assess whether PrEP with TDF/FTC taken on demand, at the time of sexual activity, could improve adherence, thereby efficacy and also improve safety and cost.
In this randomized double blind placebo controlled trial, on demand PrEP with TDF/FTC reduced the incidence of HIV by 86% in the intent to treat analysis as compared to placebo, and the only 2 participants who became infected in the TDF/FTC arm after more than a year of follow-up, had discontinued the use of PrEP months before infection.
The ANRS Ipergay study reports therefore a very high efficacy of PrEP, similar to that also reported in another PrEP study carried out in the UK among MSM with daily TDF/FTC (PROUD), which results were disclosed at the same time. Both studies have increased awareness about the real potential of PrEP and have had a strong impact on WHO and European guidelines.
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