Daily pill reduces HIV among gays

A landmark study across four continents has shown that a daily dose of an oral antiretroviral drug reduced the number of the Human Immunodeficiency Virus (HIV) infections among sexually active gay men by 44 percent, researchers said on Tuesday (Wednesday in Manila).

Even higher rates of success toward preventing the virus that causes Acquired Immunodeficiency Syndrome (AIDS) were shown among those who faithfully took the drug, said the study in the November 25 issue of the New England Journal of Medicine.

The findings were hailed by US President Barack Obama as well as leading AIDS experts as promising, even though a measure of caution remained over the limited scope of the study and the need for more methods of prevention.

“I am encouraged by this announcement of groundbreaking research on HIV prevention,” Obama said in a statement.

“While more work is needed, these kinds of studies could mark the beginning of a new era in HIV prevention. As this research continues, the importance of using proven HIV prevention methods cannot be overstated,” he added.

Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases (NIAID), which carried out the study, described the finding as “significant.”

“Those who took the drug on 90 percent or more days had 72.8-percent fewer HIV infections,” Fauci told Agence France-Presse.

The study was conducted among 2,499 men, including 29 transgendered women, between the ages of 18 and 67 who were sexually active with other men but were not infected with the virus that causes AIDS.

Known as the iPrEx HIV Prevention Study, the research was carried out from July 2007 to December 2009 in six countries—Brazil, Ecuador, Peru, South Africa, Thailand and the United States.

Participants were selected at random to take a daily dose of Truvada—a combination of 200 milligrams of emtricitabine and 300 milligrams of tenofovir disoproxil fumarate—or a placebo.

The method of taking a drug ahead of potential exposure to HIV is called pre-exposure prophylaxis (PrEP).
Truvada is US-government approved and is currently available.

Approved by FDA

The study marked the “first demonstration that using oral medications that are already FDA [Food and Drug Administration] approved before a risky exposure can decrease the likelihood that MSM [men having sex with men] could become HIV-infected,” said Kenneth Mayer, co-chairman of the Center for Global Health Policy’s Scientific Advisory Committee.

All participants were given counseling on preventing the spread of the virus as well as condoms and medical care for other sexually transmitted diseases during the course of the study.

A total of 100 HIV infections were recorded among the participants during the nearly three-year-long clinical study.

Of those, 36 were recorded among the 1,251 participants given Truvada and 64 among the 1,248 who had been given a placebo, showing that the drug reduced the risk of infection by 43.8 percent.

“This discovery alters the HIV prevention landscape forever,” said Jim Pickett, the director of advocacy at the AIDS Foundation of Chicago.

“While this level of efficacy is relatively strong, PrEP is not quite ready for prime time and work remains before this strategy is rolled out,” he added.

“However, we are thrilled to have a new prevention option beyond male and female condoms visible on the horizon,” Pickett said.

NIAID provided much of the funding, with additional money provided by the Bill and Melinda Gates Foundation.

California-based Gilead Sciences, which makes Truvada, donated the drugs used in the research.

Those who carried out the study were concerned that participants would be less cautious, thinking they were protected by the drugs, but instead the subjects reported using condoms more frequently and having fewer sexual partners.

Gay men, who are among the groups most at-risk of contracting HIV in the US, account for more than half of the 56,000 new infections each year.

One in five gay men living in 21 major US cities is infected with HIV and nearly half are unaware of it, the Centers for Disease Control and Prevention (CDC) said in a study published in September.

The New York based amfAR, The Foundation for AIDS Research, also hailed the results but noted that the prime targets of the study were high-risk gay men, so further study was needed to assess other groups, such as injection drug users, female sex workers or heterosexual women and men.

The US-based CDC said that more trials are under way to test the effectiveness of PrEP for injection drug users and heterosexuals, and those should show results “in the next few years.” –AFP