HIV Drug Reduces Transmission Among Men By Over 40%, Study Finds

A daily dose of antiretroviral medication lowered the risk of contracting HIV by more than 40% among men who have sex with men, according to a study published Tuesday in the New England Journal of Medicine, the New York Times reports.

The results of the study -- nicknamed iPrEx -- "are the best news in the AIDS field in years" and "could change the battle" against HIV/AIDS, according to the Times . Experts suspect the medication will be successful in other groups but caution that it must be tested first.

Details of Study

An international team of researchers enrolled 2,499 MSM at 11 sites in six countries to test a prevention strategy known as pre-exposure prophylaxis, which has been successful in preventing other diseases. The team was led by Robert Grant of the University of California-San Francisco Gladstone Institute of Virology and Immunology and Javier Lama of the Investigaciones Medicas en Salud in Lima, Peru . NIH and the Bill and Melinda Gates Foundation funded the study .

Half of the participants received a daily dose of Truvada, an antiretroviral drug containing emtricitabine and tenofovir, while the other half received a placebo. Both groups received counseling about condom use and safer sex practices. The researchers found that 36 participants taking Truvada contracted HIV, compared with 64 in the placebo group, representing a 43.8% reduction. They noted that the decrease was dependent on how frequently the subjects took the medication. Those who adhered to their medication at least half of the time experienced a 50.2% decline in risk, while those who took their medication at least 90% of the time saw a 72.8% risk reduction .

Caveats to Strategy

The researchers noted several limitations to the study, including that it only involved MSM and one combination of antiretroviral drugs. They said additional studies are under way to test Truvada in other high-risk groups, such as commercial sex workers and intravenous drug users, and heterosexual men and women.

Some HIV/AIDS advocates and scientists expressed concern about the cost of the strategy. Truvada costs between $12,000 and $14,000 annually in the U.S. Generic versions in developing countries cost as little as 40 cents per pill. They said they are also concerned that placing people on the drugs will speed the evolution of drug resistant strains of the virus or that people will stop using condoms .

Kevin Fenton, AIDS prevention chief at the Centers for Disease Control and Prevention, said that prophylaxis "should never be seen as a first line of defense against HIV," adding, "It's not time for gay and bisexual men to throw out their condoms" .

Grant said that the findings are "a major advance," but the strategy "will only work if people use it consistently, and the real challenge is how do you use it consistently" .

Advances in Preventive Approach

The findings follow this year's success with a vaginal microbicide gel and a proof-of-concept trial on an HIV vaccine . The microbicide study indicated that the gel protected 39% of all women testing it and 54% of those who used it consistently .

Alan Bernstein, health of the Global HIV Vaccine Enterprise, said, "This is a very exciting, dynamic time in HIV prevention research," adding, "There's clearly a growing realization that we're not going to be able to treat our way out of this epidemic" .

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Pharmac funds new HIV drug

HIV patients have a new fully funded treatment option, but have missed out on funding for another which increases the new drug's effectiveness.

The Government drug funding agency Pharmac yesterday said it would fully fund Isentress, the first in a new class of medications called integrase inhibitors.

It works by preventing HIV viral DNA inserting itself into human DNA, blocking the virus's ability to replicate and infect new cells.

"This is great news for people with HIV infection who have limited treatment options, and for the doctors treating them," said Auckland City Hospital infectious disease physician Simon Briggs.

"The funding of Isentress is timely as some of these patients have been waiting for new, funded HIV medications for some years."

The Aids Foundation welcomed the funding for Isentress, but questioned why Pharmac would not also pay for a protease inhibitor called Darunavir.

Darunavir increases the efficacy of Isentress when the two are used together.

Developed by Janssen-Cilag, Darunavir has been funded in Australia for nearly two years.

Isentress and Darunavir were approved by Medsafe last year and Janssen-Cilag gives free Darunavir to 30 people in New Zealand through a compassionate supply programme.

"The availability of Isentress is timely," said Aids Foundation spokesman Eamonn Smythe.

"Over the next few years, increasing numbers of patients will require this new class of medication.

"However, research has shown that Isentress and Darunavir, when used in combination with each other, are extremely effective in the management of HIV," he said.

A Pharmac spokesman said Darunavir was a different drug made by a different company, and was not included in the deal Pharmac struck with drug company Merck Sharp & Dohme which makes Isentress.

Any deal with Janssen-Cilag would have to be addressed separately. It was on a "to-do list" but was not guaranteed, he said.

Pharmac will also fund other new drugs after it came to an agreement with Merck Sharp & Dohme.

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Merck's AIDS Triumph

Fifteen years ago, at the height of the AIDS epidemic, Merck researcher Daria Hazuda started work on a new drug to block the HIV virus from infiltrating people's DNA.

The odds seemed grim. Merck executives at one point advised her to switch to an alternative approach being explored by rival Pfizer . And as new combinations of antiviral pill seemed to put the HIV virus in check, Hazuda herself wondered whether there was really a need for another AIDS drug. But she kept working, even as several attempts at creating the drug foundered in early tests.

Hazuda's baby, Isentress, was approved in 2006 and was Merck's fastest growing medicine last quarter. Sales of the twice-a-day pill jumped 123% to $172 million in the second quarter at a time when the overall U.S. drug market may shrink for the first time in decades. On July 9, the drug was approved as a choice for patients who are just beginning treatment. Timothy Anderson at Sanford C. Bernstein estimates sales could someday hit $2 billion a year.

"I'm glad we stuck with it," says Hazuda, now Merck's vice president of antiviral drugs. "We hear people say it has really changed their lives."

The Isentress story turns the drug industry's now-customary narrative--that small companies out-invent big ones--on its head. It's also a reminder for Merck as it braces for the inevitable culture shocks likely to result from its $41 billion merger with Schering-Plough . The prospects of a new drug are precarious, with only one in nine drugs tested in humans making it to the market. Hundreds of millions of dollars, the work of hundreds of scientists and 10 years or more will go into the effort. Yet it's often the grit and stamina of a single researcher that gets a medicine to patients.

Hazuda joined Merck in 1989 after finishing her doctorate at the State University of New York, Stony Brook. She was 30. Initially she was assigned to work on flu, but asked to be switched to HIV work. "If there was one virus worth working on, it was HIV," she says.

In 1993, virus researcher and Nobel laureate Harold Varmus, who was just about to take over as head of the National Institutes of Health, called for researchers to search for drugs to target integrase--the enzyme that Isentress would attack.

HIV copies itself by splicing into the DNA of the people it infects and being copied when their cells replicate. Integrase is the enzyme that makes the cut. Block integrase, the logic went, and the virus could not spread from cell to cell. Aside from Merck, the companies now known as GlaxoSmithKline , Sanofi-Aventis and Bristol-Myers Squibb were all searching for integrase blockers.

The first challenge was figuring out how to measure whether or not chemicals were blocking the integrase enzyme so that hundreds of different potential medicines could be tried out. She and her small team of researchers succeeded in 1993, but couldn't get any notice for their work. The Conference on Retroviruses and Opportunistic Infections, one of the biggest AIDS conferences rejected it, as did several big publications. The paper was finally published in 1994 in Nucleic Acids Research, a less prominent journal.

Then, in 1996, everything about HIV drug research changed. Results of studies combining three or four antiviral drugs at once were presented. These drug cocktails could keep HIV from ever developing into full-blown AIDS, in which the immune system fails. Scientists had commuted a death sentence.

Was there even a need for new HIV medicines? Hazuda herself was having doubts until she saw a Paul Volberding, a pioneering San Francisco doctor who had started the first program in the U.S. dedicated to treating AIDS, tell the story of a patient who had died despite the new drug cocktails. New drugs were still needed.

Just as she was getting back to work, researchers found a mutation in prostitutes and gay men that protected them from HIV infection. Other companies, including Pfizer and Schering-Plough, started developing drugs to target the gene, called CCR5. "Very senior management said I should stop working on integrase and start working on CCR5 inhibitors," Hazuda says. But she insisted the right target was integrase, part of the virus, not CCR5, which is part of the patient.

Hazuda went back to her West Point, Pa., lab. But she couldn't get her drug screen for integrase blockers to work with the robots Merck had at the time. In the summer of 1999, she and two associates squirted 250,000 different compounds by hand into plates containing the integrase enzyme. A chemical from xylaria, a fungus that grows on dead wood, blocked it. The molecule was too complicated to make into a drug, but, Hazuda says, "It provided a glimmer of hope."

Finally, a few chemicals looked like they might work. In 2000 Hazuda and her team published two landmark papers showing that integrase inhibitors could be made. The first four chemicals they tried fizzled out in early studies. The fifth was a chemical synthesized by Merck researchers in Rome who were searching for hepatitis C drugs. That became Isentress.

Isentress was approved in 2007 for patients whose viral counts were rising despite AIDS drug therapy. Sales of Pfizer's CCR5 drug are so small that the company doesn't break them out, but a once-a-day drug from Gilead is advancing through clinical trials now.

What's next? Recently Merck researchers found potential HIV drug targets by scanning the human genome. And Hazuda thinks there may be other ways to attack the virus too. "We haven't run out of ideas," she says. Merck better hope not.

Source : news.alibaba.com

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AIDS and the condom

Yellow fever, malaria and cholera, previously controlled by an adequate health program, are now raging unchecked throughout these countries. "Nigeria, one of the wealthier counties under the IMF program, is also feeling the limitations imposed upon it. Nigeria has sixty percent of all doctors and nurses in black African countries, but this healthcare force has been steadily cut down since 19, until today, Nigeria is ripe for a massive outbreak of the traditional diseases which will make it easy for AIDS to spread like wild fire.

"The condom solution is being used by the IMF for the purposes of birth control, and although extensive advertising campaigns were launched to promote their use, the quality of the condoms is so poor that as much as eighty percent of them break or leak. "The AIDS virus has entered into an explosive phase in Africa, and the same condition is fast being approached by Asian countries such as India and Thailand. By the year 2000, computerized projections show that there will be close to one-hundred million cases of AIDS in Africa, with India and other parts of Asia projected as having a combined total of ninety million cases. "Projections carried out at Los Alamos indicate that there will be a total of two-hundred million cases of AIDS in underdeveloped countries by the year 2000. There is some concern beginning to surface among the team that the AIDS pandemic may not be stoppable.

With seventy-nine to eighty percent of AIDS cases occurring in Third World countries, AIDS may well already be out of hand. There is an acceleration of the epidemic which is matched by a diminishing of responses. "Almost seventy percent of all AIDS cases in Africa are among heterosexuals. The same holds true for Asia and Brazil. By the year 2000 the number of people in Asia suffering from AIDS will equal those of Africa. AIDS has become the killer of the poor, thanks to the cuts in standards of health care and lowered nutrition standards to meet IMF demands. "The latest report from WHO which is not being circulated is that governments of poor countries have given up the struggle to contain AIDS.

This applies particularly to India, where the AIDS epidemic is exploding with a virulence unmatched in Western countries. "From the point of view of senior virologists, there is no cure in sight for AIDS. The view taken by Dr. Jonas Salk that a means must be found of boosting the human immune system rather than trying to develop antibodies that can kill the AIDS virus appears to be gaining ground among those members of the medical profession who are realizing that AIDS is a created virus. "Underlining the findings of how the IMF is affecting the situation, a new threat, that of a highly virulent form of tuberculosis is now taking hold in poor countries and among the poor in the United States.… A report compiled by the CDC which is not being circulated says that the incidence of the new drugresistant strain of bacilli is now twice as high since the last study was done in 1984.

Tuberculosis has increased by twenty percent in the U.S. since 1985. Every TB patient is a target for the AIDS virus, and those with AIDS are highly susceptible to contracting tuberculosis. The ramifications are not difficult to comprehend; a twin plague of the most virulent kind is about to explode with great force in the overcrowded inner cities of America, and has already begun. "To confirm the ratio of tuberculosis to conditions of poverty, a recent study of the homeless was undertaken by a Los Alamos team.

The results bear out the "poor man's disease" label in that homeless people are forty times more likely to contract tuberculosis than those in comfortable circumstances. The conclusion drawn is that the spread of TB is accelerating at a faster rate than ever seen before, and that the outbreak of lethal epidemics are at hand." AIDS is the key to Global 2000 plans, because of its effectiveness in attacking the lungs. Imagine a searing epidemic of AIDS, followed by an epidemic of tuberculosis and then pneumonic plague, like the one that killed hundreds of thousands in Manchuria and eastern India during the period 1910-1911 and again in Europe in 1919-1921. (66 of ) When the AIDS virus becomes localized in the lungs, it is spread by respiratory discharges, such as coughing and sneezing, and in favorable climatic conditions becomes a highly contagious infectious disease.

One of the favorable conditions for the spread of AIDS is crowded dwelling space, inadequate ventilation and the weather, especially when the weather is cooler, as it is during winter in the Middle East, India and Pakistan, Malaysia and the Philippines. Pneumonic Plague would thrive in those conditions. It is not difficult to envision the rapid spread of tuberculosis in the wake of AIDS, followed by pneumonic plague throughout Africa, given the conditions so graphically described by Dr. Debret in his 1989 Paris Match interview, and spreading from Africa to India, the Philippines, Malaysia and China.

The United Nations, backed by military forces of the United States, could effectively quarantine these nations, making it difficult for anyone to escape the "cordon sanitaire" set up by the World Health Organization or some other One-World institution. Millions would be left to die. Somalia was a "test case." After a new mosquito-borne malaria that acts against the immune system was released into the population, U. N. troops were sent in to test the "cordon sanitaire." As this strategy moves forward, loans from the International Monetary Fund and the World Bank to Third World countries will increasingly require governments to enforce specific plans to diminish their populations. Contraceptives and severe penalties for families exceeding certain numbers are a part of this regimen.

McNamara will emphasize four global environmental problems created by overpopulation: the loss of bio-diversity, acid raid, the destruction of the ozone layer and changes in the climate. "All are functions of rising population levels," he has stated, "and increasing consumption per capita." Although he has always neglected to mention that the huge consumption levels that are dangerous to the environment are among the rich; not the poor. It's not the poor of the world who burn millions of gallons of petroleum flying around on private jets. It's not the poor of the world who are burning a hole in the ozone layer. It's not the poor of the world who are bulldozing the Rain Forests to create new wealth.

Try to imagine the vastness of the earth's resources burned and consumed to support the lifestyles of any one large clan of superrich like the Kennedys or Rockefellers or Sabahs of Kuwait compared to the necessities that sustain the simple lifestyle needs of the poor villages around the world. As McNamara and his team were working on their Global 2000 plan, the World Health Organization in Geneva was sending out directives to their branches, demanding "a significant increase in the number of viral vaccines without a reduction in quality or potency." The pressure will be on in the second half of the 1990's to speed up the pace at which they rid the planet of its "useless eaters."

The Catholic Church can and will use its vast resources to fight the Global 2000 plan for mass sterilization and contraception. But not even the Catholic Church would dare blame the Olympians for the deaths of tens or hundreds of millions from "natural causes." The AIDS epidemic will only be a part of that.

The Global 2000 Committee is also counting on an epidemic of tuberculosis, which has already infected more than a billion people. The new TB strain is resistant to all known methods of treatment, and the death rate from the new tuberculosis bacilli is ten times greater than from previously known types of (67 of ) the disease. This new strain may well be part of the process designed to "speed up" the death rate. But as long as the world believes that AIDS and this new strain of TB were created by nature, those deaths can only be lamented as the tragic result of "natural causes."

How many people will allow themselves to believe the truth? How many will demand an honest answer to the question: Was the AIDS virus really created in our own Chemical and Bacteriological Warfare labs? Perhaps not enough. As Dr. John Seale said: "Doubtless most people will dismiss the suggestion that the AIDS epidemic in the United States may be the result of an act of deliberate biological warfare as worthy only of a fictional plot by Ian Fleming. But it is certainly no less plausible, scientifically, than the hypothesis currently favored by molecular biologists. It may even be true, though strange, but truth is always stranger than fiction." Dr. Seale sadly concluded: "The greatest coverup of any disease in history is in progress."

The participants in the coverup, says Dr. Seale, include the editors of medical and scientific journals who "have misled their professional colleagues about the nature and severity of the AIDS epidemic…By selective acceptance or rejection of original papers and letters, and by selecting authors to write 'safe' editorials and review articles, they have perpetuated dangerous misconceptions." But he knows what his colleagues know: "Every biological scientist who has dispassionately studied the virus and the epidemic knows that the origins of the virus could lie in the development of modern biology, just as the origins of the nuclear bomb lie with modern physics.… Most who see it keep quiet, but increasing numbers are talking privately though they still lack the moral courage to speak out in public. They still hope it is a nightmare which will vanish with tomorrow's dawn." But the nightmare won't vanish with the dawn. If we pretend it will just go away, the worst is yet to come. And, as Schopenhauer, the philosopher, said, so on until the worst of all.

Source : www.web-articles.info

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Two New AIDS Drugs May Reach Market

There’s new hope for people living with HIV/AIDS whose medications have begun to stop working against the always-adapting virus. Two new classes of drugs may be about to come into use.

A Feb. 28 story in The New York Times cited the University of Pittsburgh’s Dr. John W. Mellors, who serves as a consultant to pharmaceuticals firms, as drawing parallels between the new drugs and the advent of the so-called "cocktail" of medications that dramatically improved survival rates, adding quality years to the lives of HIV positive people in the 1990s.

Mellors, speaking at the 14th Annual Conference on Retroviruses and Opportunistic Infections, said, "This is really a remarkable development in the field," the article reported.

Another consultant, Dr. Scott Hammer, was quoted as saying that the new treatment options would "provide extended years of meaningful survival to patients." Dr. Hammer is Columbia University Medical Center’s chief of infectious diseases, the article noted.

The new medications are called maraviroc and raltegravir.

The pharmaceutical firm Pfizer has applied to the FDA for approval to market maraviroc, which works not by attacking the virus directly, but rather by blocking the proteins on human cells that the virus uses to gain access to the cells’ interiors, where it hijacks the cell’s own reproductive machinery, turning the cell into a factory for new copies of the virus.

If the virus cannot use those sites to attach to and enter the cell, its reproductive process is interrupted. The article noted that maraviroc is the first drug to use this approach to be developed that does not seem to entail grave side effects, following the 1996 discovery of the protein in question, known as CCR5.

In a minority of cases, the article noted, a strain of the HIV virus will use a different protein, CXCR4, instead of CCR5 to gain access to the cells’ interiors; a test will be required to ensure that the patient’s particular strain of HIV uses CCR5 before maraviroc will be prescribed.

Other firms had attempted to exploit the same protein-blocking approach, but the drugs they developed seemed to involve dangerous side effects.

No such consequences have been noted thus far with maraviroc, though trials are ongoing to determine whether there might be a risk of longer-term side effects.

In maraviroc’s clinical trials, 40% of trial participants saw their viral loads diminish to undetectable levels after four months on maraviroc, despite the virus having become resistant to the participants’ previous drug regimens.

The other new drug, raltegravir, was developed by Merck, which plans to submit an application for FDA approval later this year.

The Merck drug also acts to interrupt the virus’ reproductive cycle: in this case, by blocking the action of a crucial enzyme that allows the virus to insinuate its own genetic sequence into the host cell’s DNA, causing the host cell to create more HIV.

Two Merck studies resulted in undetectable levels of HIV in 60% of trial participants in whom the virus had adapted to older medications, the article reported.

The article noted that in many cases, the virus’ adaptation to older medications was accelerated by individuals neglecting to take their medications on schedule.

Both raltegravir and maraviroc, if approved, would be taken in conjunction with older drugs, the article reported.

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