What is the iPrEx Study and what was its purpose?

The iPrEx study was a Phase III study designed to determine whether emtricitabine/tenofovir/ (FTC/TDF), a drug that is already being used to treat people living with HIV infection, may also help prevent HIV infection in men who are HIV negative when combined with safer sex counseling and condom use.

The study was conducted among 2,499 HIV-negative gay men, male to female transgendered women and other MSM at 11 sites in Brazil, Ecuador, Peru, South Africa, Thailand, and the US.

The study showed that when used regularly and consistently, FTC/TDF helped to protect this group from HIV, compared to those in the placebo group.

Why are the study and its findings important?

The iPrEx study is important because it is the first large efficacy trial to evaluate the use of PrEP in MSM in Africa, Asia, and North and South Africa and find that daily use of an anti-retroviral in a pill can protect against HIV infection.

This is a monumental milestone in the history of HIV prevention research.

Did the study find that the FTC/TDF pill was safe to use for prevention?

Overall, the tolerability and safety reported by the study participants was good. There were some reports of nausea in participants who took FTC/TDF compared to placebo, although many of the symptoms were observed to have resolved over time.

It's important therefore to continue to study the pill in follow up studies to understand how safe and tolerable it is with long-term use for someone who is not HIV positive.

Is the pill available now?

The pill is currently available for treatment of HIV only. The next step will be to conduct and follow existing trials that are testing the therapy in women. Findings from these trials will be an important milestone in demonstrating success and the move toward licensure of both the gel and oral pills for women who are most at risk for HIV infection.

Will it work in women?

We don't know. The trial did not study the effectiveness of FTC/TDF in women. And, since you cannot take trial results from one patient population and apply them to another, it is imperative that we examine the efficacy of PrEP specifically in women who are at risk of HIV infection.

There are a number of clinical trials currently underway testing the effectiveness of FTC/TDF and tenofovir (TDF) alone in different community groups considered to be high risk -- women, injecting drug users and couples where one partner is HIV positive and the other is not. The results from the first of these trials will be available in 2013 from the VOICE trial, testing TDF alone and FTC/TDF as well as the TDF-gel in women in different countries in Africa.

Why is it important to know if a pill can help prevent HIV in women?

Women around the world continue to bear the greatest burden of HIV. In Sub-Saharan Africa, 60 percent of all new infections occur in women. Women also need to be offered options so they can protect themselves from HIV, whether in the form of a gel, a pill or a slow-release vaginal ring. Just as we do with contraception, we need to make different options available to women, so they can choose what best suits them and their lifestyle.

So, while the iPrEx findings are positive and offer hope for MSM -- and offer a scientific basis for hope in women -- we must continue to stay focused and ensure that access to new and existing HIV prevention options are available for women.

What is the VOICE Study?

The Vaginal and Oral Interventions to Control the Epidemic (VOICE) study is a major HIV prevention trial evaluating two different approaches for preventing sexual transmission of HIV in women. It is funded by the US National Institutes of Health (NIH) and conducted by the Microbicide Trials Network (MTN). VOICE is studying whether the same antiretroviral (ARV) medications used successfully for the treatment of HIV are safe and effective for HIV prevention, used either as a vaginal microbicide or an oral tablet.

VOICE -- also known as MTN-003 -- is the first effectiveness study of a microbicide that women use every day and the only trial evaluating both a gel and a tablet in the same study.

In addition, the study seeks to determine which of these routines women are more likely to follow: taking a tablet by mouth once a day, an approach known as oral pre-exposure prophylaxis (PrEP), or applying a vaginal microbicide gel every day.

Results from VOICE are due in 2013.

What will Global Campaign do now that we have these results?

We will continue to advocate for women at greatest risk of HIV, wherever they may be, and work to ensure that safe and effective prevention tools are made available to them.

As an advocate for HIV prevention, what should I do?

Inform your community about this important trial result. If you work with MSM communities in Africa or anywhere else or with women at high risk of HIV, be informed of what the study means for them.

We invite you to work with the Global Campaign to support our efforts in making HIV prevention a safe and effective reality for women, and all those vulnerable to HIV.

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