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iPrEx: First-Ever PrEP Efficacy Study Published

By Paul Sax, M.D.

November 23, 2010

iPrEx: First-Ever PrEP Efficacy Study Published
It's been quite the year (plus a month) for HIV prevention research.

That glimmer of hope from the Thai vaccine trial. The striking effect of HIV-treatment as prevention. The positive results of the CAPRISA vaginal microbicide study, which were presented to rapturous applause this summer in Vienna.

And today, the iPrEx study is published, which shows that giving TDF/FTC to HIV-negative, high-risk men who have sex with men (MSM) reduces their risk of acquiring HIV by 44%. It's the first efficacy study of pre-exposure prophylaxis (PrEP) and will undoubtedly generate plenty of discussion.

For a detailed scientific analysis of the trial, two HIV prevention experts have already provided their commentary, Nelson Michael in NEJM and Raphy Landovitz in Journal Watch AIDS Clinical Care. I highly recommend both.

But every HIV specialist/Infectious Disease doctor will have thoughts on this important study, so in no particular order, here are mine:

Weird spelling notwithstanding, iPrEx is the first of several studies of PrEP, and its publication is a landmark event. The study continues with all subjects now receiving TDF/FTC (or FTC-TDF, grrr); hence there are more data to come -- not only from iPrEx but from the multiple other ongoing HIV prevention studies.

In fact, this timeline of HIV prevention research suggests that the next few years could, amazingly, be even more exciting than this past one.

Paul Sax is Clinical Director of Infectious Diseases at Brigham and Women's Hospital. His blog HIV and ID Observations is part of Journal Watch, where he is Editor-in-Chief of Journal Watch AIDS Clinical Care.

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