WEDNESDAY, Oct. 1 (HealthDay News) -- New research offers more evidence that a new class of AIDS drug can provide major benefits for certain patients who have become immune to existing medications.

The U.S. Food and Drug Administration approved maraviroc, known by the brand name Selzentry, in August 2007 after a 24-week study showed it had beneficial effects. It was the first new HIV oral medication approved in more than a decade.

The new study followed the patients for another 24 weeks, and found that more than 40 percent of them had reduced levels of the AIDS-causing HIV virus in their blood.

"We're really able to do something we haven't been able to do before, essentially rescue someone with drug-resistant virus and gain control of their HIV infection," said principal investigator Dr. Roy Gulick, director of the Cornell HIV Clinical Trials Unit at Weill Cornell Medical College in New York City.

Since the 1990s, new generations of drugs have made major strides in treating the virus that causes AIDS. Patients are often able to control the levels of the virus in their bodies and live for years.

However, the virus has the ability to mutate and evolve, and it's often able to adjust to resist the killing powers of medications. Some people also become newly infected with strains of HIV that are already immune to certain drugs.

"Roughly, between a quarter and a third of patients [are resistant] to the classic classes of drugs," Gulick said. "These are patients who really need treatment options."

The new study, published in the Oct. 2 issue of the New England Journal of Medicine, followed 1,049 HIV patients who were resistant to three classes of HIV drugs. Some patients received doses of maraviroc, while others received a placebo. The study was funded by Pfizer Inc., the maker of the drug.

Between 42 percent and 47 percent of the patients taking maraviroc reached reduced levels of the AIDS virus in their bodies, compared to 17 percent of the placebo group.

"There were no apparent side effects or toxicity differences in patients that got maraviroc vs. placebo," Gulick said. "It looked safe and generally well-tolerated over 48 weeks."

The drug works by preventing the AIDS virus from binding to a receptor on immune cells known as CCR5. Some people are born without the receptor and are naturally resistant to the AIDS virus.

There are caveats with maraviroc: Doctors must give a $1,900 test to patients to make sure their strain of HIV would be susceptible to the drug, Gulick said. Also, researchers must follow patients on maraviroc to see if any unusual medical problems affect them over time, he said.

Dr. Barry S. Zingman, medical director of the AIDS Center at Montefiore Medical Center in New York City, and one of the doctors taking part in the study, said he has had good experiences prescribing maraviroc.

However, "many patients who need a new treatment option cannot use it" because they don't have the necessary strain of HIV, said Zingman, who has received research grants to study the drug.

In addition, he said, "there are significant interactions between maraviroc and other medications for HIV infection, making it a bit complicated to prescribe in the combination regimens that are standard around the world."

More information

Visit the U.S. Food and Drug Administration for the list of the latest approved HIV drugs.

FRIDAY, Sept. 26 (HealthDay News) -- As the number of countries reporting intravenous drug use has increased over the last decade, a new study suggests that as many as 3 million of these addicts may be HIV-positive.

The data, published online in The Lancet, found the proportions of injecting drug users (IDUs) who are HIV-positive exceeds 40 percent in nine countries. Yet, the variation between countries is extreme.

For example, in the United States, just less than 1 percent of 15- to 64-year-olds are IDUs, 15.6 percent of whom are HIV positive; meanwhile in Argentina, the proportion of IDUs is far lower (0.29 percent), but the proportion of those with HIV is more than triple at 49.7 percent. In the United Kingdom, though, 0.39 percent of the same age group inject their drugs yet only 2.3 percent are thought to be HIV positive.

"Areas of particular concern are countries in southeast Asia, eastern Europe, and Latin America, where the prevalence of HIV infection among some subpopulations of people who inject drugs has been reported to be over 40 percent," the authors wrote.

While noting a dearth of information from Africa, they added that a "constellation of risk factors exists for the development of injecting drug use, as has occurred elsewhere."

The researchers estimate that almost 16 million people worldwide inject drugs. They identified 148 countries with IDU and 120 of those having HIV among IDUs, up notably from a 1998 review that found 29 countries with IDU and 103 with HIV among IDUs.

In an accompanying commentary in The Lancet, Kamyar Arasteh and Don Des Jarlais, of Beth Israel Medical Center's Baron Edmond de Rothschild Chemical Dependency Institute in New York, call for massive worldwide intervention.

"The one optimistic aspect of this rather gloomy situation is that, if HIV-prevention efforts are implemented on a large scale when prevalence is low in injecting drug users, it is possible to avert HIV epidemics in users. Thus it should be an imperative for both resource-constrained countries and international donors to implement large-scale evidence-based programs for HIV-prevention whenever there is an indication of a developing injecting-drug-use problem," they concluded.

More information

The U.S. Centers for Disease Control and Prevention has more about HIV/AIDS.

FRIDAY, Sept. 19 (HealthDay News) -- People who are socially isolated may literally feel left out in the cold, suggest Canadian researchers who examined whether social exclusion may generate physical feelings of coldness.

The University of Toronto psychologists divided volunteers into two groups. One group recalled a personal experience in which they'd been socially excluded, while the other group recalled an experience in which they'd been accepted into a group.

Participants in both groups were asked to estimate the temperature in the room, on the pretense that maintenance staff wanted that information. Their estimates ranged from 54 degrees F to 104 degrees F. Those told to think about a socially isolating experience gave lower estimates of the room temperature.

"We found that the experience of social exclusion literally feels cold. This may be why people use temperature-related metaphors to describe social inclusion and exclusion," study co-author Chen-Bo Zhong said in an Association for Psychological Science news release.

In another test, the volunteers played a computer-simulated ball tossing game designed to toss the ball to certain players many times, while leaving others out of the game.

After playing the game, the participants were asked to rate the desirability of certain foods and beverages -- hot soup, hot coffee, crackers, an apple, and a cold soft drink. The "unpopular" participants who'd been left out of the computer ball game were much more likely to want either hot soup or hot coffee -- a desire presumably caused by a physical feeling of coldness.

"It's striking that people preferred hot coffee and soup more when socially excluded. Our research suggests that warm chicken soup may be a literal coping mechanism for social isolation," study co-author Geoffrey Leonardelli said in the news release.

The findings were published in the September issue of the journal Psychological Science.

More information

The American Academy of Family Physicians explains how emotions can affect your health  .

FRIDAY, Aug. 29 (HealthDay News) -- Just a few glasses of wine over a short period in early pregnancy may cause fetal problems, suggest researchers from the Medical College of Georgia.

The initial signs of fetal alcohol syndrome, which affects one in 1,000 babies, include facial malformations such as a flat and high upper lip, small eye openings, and a short nose. Researchers are investigating whether these signs can help determine how much alcohol at what point in pregnancy may cause fetal problems.

Supported by a grant from the March of Dimes, Erhard Bieberich, a biochemist in the Medical College of Georgia Schools of Medicine and Graduate Studies, and his colleagues are focusing on how alcohol consumption affects neural crest cells, which help form the upper part of the skull, in mice.

Specifically, the researchers are comparing cell death in mice following different levels of alcohol consumption to the cell death that occurs during normal development.

There is evidence that the equivalent of just a few glasses of wine over an hour in the first few weeks of fetal life can increase cell death.

"It's well known that when you drink, you get a buzz. But a couple of hours later, that initial impact, at least, is gone," said Bieberich in a Medical College of Georgia press release. "But, your fetus may have experienced irreversible damage."

The U.S. Centers for Disease Control and Prevention recommends that pregnant women and sexually active women not using effective birth control refrain from drinking.

More information

The Nemours Foundation has more about fetal alcohol syndrome  .