Groundbreaking research paves way for HIV prevention drug approval

July 12, 2012 By Jeff Hodson
The Thika, Kenya puppets used in public education programs to recruit couples to the HIV prevention study, pose with researchers Dr. Nelly Mjugo and Dr. Jared Baeten.

(Medical Xpress) -- For the first time, the U.S. Food and Drug Administration is considering approving a drug that helps prevent someone from acquiring HIV. It’s called Truvada, and has been approved for use since 2004 to treat infected people.

Now it has been shown to protect healthy people who are exposed to . The UW's International Clinical Research Center, within the Department of Global Health, played a key role in examining the drug’s effectiveness for HIV prevention.

Researchers Connie Celum and Jared Baeten led a study, published this week in the New England Journal of Medicine, of pre-exposure prophylaxis among heterosexual couples in Kenya and Uganda. One partner had HIV (and was not yet eligible for HIV treatment) and the other partner did not have HIV. Uninfected partners were given either Truvada or Tenofovir (both antiretroviral drugs) or a placebo.

The study, called Partners PrEP, found that individuals at high risk for HIV had far fewer infections when they took a daily tablet of HIV medication. The FDA has announced that it will make a decision about approval for Truvada for HIV prevention by mid-September, to give sufficient time to review the strategies for monitoring PrEP.

Celum, the center’s director and a professor of global health and medicine, talks about the impact of this ground-breaking research.

Q: What is the potential impact of Truvada in the fight against HIV?

We’ve been on a 30-year search for successful HIV prevention strategies. In addition to condoms, new strategies that recently have been shown to offer protection include male circumcision and treatment for those who are HIV-positive. Truvada as pre-exposure prophylaxis is a new tool for keeping people uninfected.

Q: What’s the extent of the HIV epidemic?

In the US, about 1.2 million people have HIV, with 50,000 new infections each year. That’s stayed stable for the last 15 years, which is part of the reason the FDA was convinced we needed new tools. Globally, there are more than 2 million infections each year. Ninety percent of the infected people live in Africa.

Q: The drug is expected to cost about $14,000 a year. How can people afford it?

That’s U.S. pricing. It’s available generically overseas, and Gilead [the US drug maker] has discounted pricing in low and middle-income countries. The cost of the drug, either using generic products or discounted pricing provided to low-income countries, is about $100 a year. In the US, a key issue is going to be insurance coverage. It’s not cheap, but it’s cheaper than the cost of lifelong treatment for HIV if someone becomes HIV infected.

Q: Who would use the drug?

Men who have sex with men, discordant couples [where one partner has HIV and one doesn’t] and women who are at risk. If the FDA approves Truvada for HIV prevention, this decision will affect only the U.S. It has broader repercussions; many other countries, including in Africa, will see the FDA decision as a strong signal that the drug is safe and effective.

Q: How does Truvada work?

In some ways, it’s like malaria prophylaxis. You use it before you go into a high-prevalence setting, and if a mosquito with the malaria parasite bites you, you don’t get infected. The idea is that if you have the drug in your body, you prevent HIV infection from being established.

Q: Are there any side effects?

We did very intensive safety monitoring. Kidney problems were very rare. We found no difference in bone fractures. Lastly, we observed a low percentage with mild gastrointestinal symptoms in the first month, which went away by the second month. They were relatively mild and did not cause people to stop taking the drugs.

Q: The drug needs to be taken every day. Won’t that be difficult for some people?

We need to make it clear this isn’t something for everyone. People need to be at sufficient risk to benefit from it. So far, the data from the trials suggests that people either took it or they didn’t take it. There weren’t a lot of intermittent users. The risk of resistance is if people take this drug when they are in the process of becoming infected. The other concern would be if people took it sporadically or they weren’t tested frequently enough for HIV.

Q: What role has your research played in the FDA’s review?

The FDA asked Gilead to include our Partners PrEP study data as part of its application. Over the last six months we’ve worked hard to get the data analyzed and submitted. It was an important part of the package. Although it comes from populations outside the US, I believe it was an important demonstration of efficacy. It was a landmark study. This was the largest trial of pre-exposure prophylaxis and one of the largest HIV prevention trials ever. It required highly motivated couples and staff. The couples achieved higher levels of retention and adherence than has been observed in most studies. It takes a huge effort and focused team to accomplish that. Our trial had the highest efficacy (75 percent for Truvada and 67 percent for Tenofovir) of any of the studies. It was the only study that had large numbers of heterosexual men as well as women.

Q: How many people took part?

Over 4,700 couples at nine sites in Kenya and Uganda. We began the study in July 2008.

Q: What’s next?

We are continuing the study through the end of this year, so we will have additional data since July 2011, when the placebo arm was offered PrEP. We’ll also be doing demonstration projects focusing on discordant couples in East Africa. We have funding at this point from the National Institutes of Health and the Gates Foundation.

Q: How close are we to an HIV vaccine?

The process has been a lot more complicated than we envisioned. We need to continue to use the tools we have while we continue to pursue a vaccine. Unfortunately, there’s not going to be a silver bullet on its own that is going to be a game changer. No strategy is 100 percent effective. If we can get really high coverage of testing, if we can get people into care, get people treated at earlier stages of HIV infection, and in Africa scale up male circumcision and offer pre-exposure prophylaxis for target populations, then I think the combination of these partially effective strategies can be a game changer while we continue the pursuit of an HIV vaccine.

Explore further: Hope for more options in couples where one partner is HIV positive

More information:

Related Stories

Hope for more options in couples where one partner is HIV positive

November 15, 2011
In sub-Saharan Africa, couples in long-term relationships where one partner is HIV-positive and the other is HIV-negative (HIV serodiscordant couples) could benefit from anti-AIDS drugs (antiretroviral therapy) given either ...

US delays decision on first drug to prevent HIV

June 9, 2012
(AP) — Drugmaker Gilead Sciences Inc. says federal health regulators have delayed a decision on whether to approve its drug Truvada as the first pill that prevents HIV infection.

Pivotal study in Africa finds that HIV medications prevent HIV infection

July 13, 2011
In a result that will fundamentally change approaches to HIV prevention in Africa, an international study has demonstrated that individuals at high risk for HIV infection who took a daily tablet containing an HIV medication ...

Pills to prevent HIV raise many questions: studies

July 11, 2012
Various trials examining the use of anti-retroviral drugs in healthy heterosexuals as a way to prevent HIV have shown drastically different results, research showed Wednesday.

Drugs used to treat HIV also reduce risk of HIV infection

July 10, 2012
People at high risk of HIV infection can reduce their risk of acquiring the disease by taking antiretroviral drugs, according to Cochrane researchers. In an update of a systematic review first published in 2009, the researchers ...

Recommended for you

Three-in-one antibody protects monkeys from HIV-like virus

September 20, 2017
A three-pronged antibody made in the laboratory protected monkeys from infection with two strains of SHIV, a monkey form of HIV, better than individual natural antibodies from which the engineered antibody is derived, researchers ...

Fighting HIV on multiple fronts might lead to vaccine

September 20, 2017
A combination antibody strategy could be the key to halting the spread of HIV, according to results from two promising animal studies.

HIV-AIDS: Following your gut

September 18, 2017
Researchers at the University of Montreal Hospital Research Centre (CRCHUM) have discovered a way to slow viral replication in the gastrointestinal tract of people infected by HIV-AIDS.

Study finds cutbacks in foreign aid for HIV treatment would cause great harm

August 30, 2017
Proposed reductions in U.S. foreign aid would have a devastating impact on HIV treatment and prevention programs in countries receiving such aid, an international team of investigators reports. In their paper published online ...

Cancer drug can reactivate HIV

August 24, 2017
People living with HIV must take a combination of three or more different drugs every day for the rest of their lives. Unfortunately, by following this strict treatment plan, they can suffer from side effects ranging from ...

New injectable antiretroviral treatment proved to be as effective as standard oral therapy

August 3, 2017
Intramuscularly administered antiretroviral therapy (ART) may be as effective for HIV treatment as current oral therapies. This is the main conclusion of a Phase II clinical trial carried out by 50 research centers around ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.