1. Headline
  1. Headline
By
updated 4/18/2011 10:29:24 AM ET 2011-04-18T14:29:24

Researchers are stopping a study that tests a daily pill to prevent infection with the AIDS virus in thousands of African women because partial results show no signs that the drug is doing any good.

  1. More from TODAY.com
    1. Play nice: 4 ways to teach kindness and raise kids who aren't jerks

      Every parent has probably said, “play nicely” or “be kind to your sister.” And most of us agree that we want to raise cari...

    2. Natalie and Jenna: We can be the next Thelma and Louise — 'minus the ending'
    3. Renee Zellweger selling Connecticut country home
    4. 5 things I wish my boss knew about fatherhood
    5. Tying the knot

Women taking Truvada, made by Gilead Sciences Inc., are just as likely to get HIV as other women who have been given dummy pills, an interim analysis of the study found. Even if the study were to continue, it would not be able to determine whether the pills help prevent infection, since the results are even this far along, researchers said.

The finding is disappointing because another study last fall concluded that Truvada did help prevent infections in gay and bisexual men when given with condoms, counseling and other prevention services. Many AIDS experts view that as a breakthrough that might help slow the epidemic.

Family Health International, a nonprofit involved in AIDS research, announced the new results on Monday. The group launched the study two years ago and had enrolled about half of the 3,900 women intended in Kenya, Tanzania and South Africa. As of last week, 56 new HIV infections had occurred, half in each group.

No safety problems were seen with Truvada. However, women taking it were more likely to become pregnant than those on dummy pills.

"That's both a surprising finding and one that we can't readily explain" by what is known so far about Truvada's effects on women using hormonal contraceptives, said Dr. Timothy Mastro of Family Health International. The study was sponsored by the U.S. Agency for International Development and the Bill & Melinda Gates Foundation. Gilead provided the drugs for the study.

Truvada already is sold for treating HIV. It's a combination of two drugs, tenofovir and emtricitabine, or FTC, made by California-based Gilead Sciences Inc.

Using it or its components for prevention is still "very promising," Mastro said, although benefits and risks may vary by gender and by the way the virus is spread — sex between men and women or riskier anal sex among men, for example.

Last year, a study in South Africa found that a vaginal gel spiked with tenofovir cut in half a woman's chances of getting HIV from an infected partner. Protection was greater for those who used it most faithfully.

A similar effect was seen in the study of Truvada in gay men. The drug lowered the chances of infection by 44 percent, and by 73 percent or more among men who took their pills most faithfully. The U.S. Centers for Disease Control and Prevention recently gave advice to doctors on prescribing Truvada along with other prevention services for gay men, based on those encouraging results.

In the new study, "it's difficult to understand why they did not see protection," but blood samples may tell more about whether it's related to how faithfully women took the pills, said Dr. Robert M. Grant of the Gladstone Institutes, a private foundation affiliated with the University of California, San Francisco.

He led the study of Truvada in gay men and said, "we are very confident that this approach is useful" for them.

The new study's result "must be seen as what it is — the closure of a single trial in a field that has generated exciting results in the recent past," said Mitchell Warren, head of the AIDS Vaccine Advocacy Coalition, a nonprofit group that works on HIV prevention research.

Two other large studies testing AIDS drugs for prevention are under way in Africa, in heterosexual women and in couples where one has the virus and the other does not. Results are expected within two years. The studies have mostly been in countries with high rates of new infections because that makes it easier to see whether a prevention measure is having an impact.

Truvada costs $5,000 to $14,000 a year in the United States, but as little as $140 a year in some poor countries where it's available in generic form.

Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Discuss:

Discussion comments

,

More on TODAY.com

  1. Monkey Business Images / Shutterstock

    Play nice: 4 ways to teach kindness and raise kids who aren't jerks

    7/24/2014 7:05:14 PM +00:00 2014-07-24T19:05:14
  1. Watch the full ‘Fifty Shades of Grey’ trailer: What we couldn’t show on TV

    “Fifty Shades of Grey” fans, you’ve come to the right place. 

    7/24/2014 12:30:07 PM +00:00 2014-07-24T12:30:07
  2. video ‘Fifty Shades’ stars give first look at steamy film

    video Stars Jamie Dornan and Dakota Johnson offer TODAY viewers a sneak peek at the highly anticipated film. When Savannah Guthrie told Dornan that viewers had asked if he'd do the interview shirtless, he said, “I would have considered it.” 

    7/24/2014 5:22:44 PM +00:00 2014-07-24T17:22:44
  3. Not a date movie: Why ‘Fifty Shades’ a girls’ night hit

    Even though the film is opening on Valentine's Day — the biggest date night of the year — women are likely to turn the movie into a social event.

    7/24/2014 1:22:41 PM +00:00 2014-07-24T13:22:41
  4. Universal Pictures
  1. Air Algerie flight remains missing 

    After reports that the commercial jet that went missing on Thursday over western Africa had been found, French President Francois Hollande stated that “no trace of plane has been found yet." 

    7/24/2014 2:47:05 PM +00:00 2014-07-24T14:47:05