The renewed interest in PrEP comes after two high-profile trials of a vaccine candidate produced by Merck were stopped early in 2007. At least 2.7 million people around the world are HIV-positive, according to the United Nations. Public health experts believe an arsenal of effective prevention tools against HIV is needed to curb its spread, because not everyone will practice existing methods known to work, such as condom use, monogamy between uninfected partners, and abstinence. Trials of potential microbicides, a woman-controlled prevention method that would work similarly to spermicides and other topical birth control methods by blocking or killing HIV during sex, have also been disappointing so far and may not be practical for all women to use. PrEP would offer an alternative.
The trials are investigating whether a daily dose of one of two antiretroviral drugs—either tenofovir disoproxil fumarate (TDF), commercially known as Viread, or Truvada (TDF combined with emtricitabine) can protect people at high risk of HIV from becoming infected.
Antiretroviral drugs, which stop retroviruses like HIV from replicating, are used to treat HIV-positive people. In certain cases they are also employed as a prophylactic to prevent the transmission of the virus from a mother to her newborn or to reduce the chance that someone who has been exposed to the virus, such as through rape or a needle prick, becomes infected.
TDF and emtricitabine are being tested for use as PrEP because they are known to cause low levels of resistance and fewer side effects, and because they remain in the bloodstream for a long time.
Results from studies in gay American men and injecting drug users in Thailand may be available next year. But the first full study testing whether PrEP stops the transmission of HIV through heterosexual sex (the main driver of the epidemic in Africa), which is being carried out in Botswana with plans to expand into South Africa, is not expected to yield results until 2011. And the three biggest trials, involving a total of 12,000 people across Africa, will not be complete until at least 2012.
Researchers are already looking forward to the potential issues that will arise if PrEP is found to be effective, such as whether the use of antiretroviral drugs as preventives will lead to increased resistance or how it could affect the future treatment options of people who later become infected.
If it does work, the public health community will also have to grapple with the tough question of when and how to use PrEP as well as how to balance the need to keep drug-resistant strains of HIV from thriving in the population while saving lives in the short term.
"PrEP has to be implemented as part of a formal program with guidelines and a funding stream. We have to start planning for that," says Lynn Paxton, a PrEP researcher at the U.S. Centers for Disease Control and Prevention.
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Add Comment"Natures methods of keeping populations from exploding beyond their means is disease and famine."
Reply | Report Abuse | Link to thisHmmm.
Leave it to a french AIDS organization to shut down trials of a lifesaving HIV drug.
Reply | Report Abuse | Link to thisthat would be nice, but there are not too many people in Africa, there is underdevelopment, that Aids appeared after whites said there are too many blacks is frightening what kind of evil is that
Reply | Report Abuse | Link to thisthat would be nice, but there are not too many people in Africa, there is underdevelopment, that Aids appeared after whites said there are too many blacks is frightening what kind of evil is that, at least today people understand with knowledge the earth can accommodate more people, the only people who will remain in the past are the Canadians, to them only whites have brains, that is why Aids will be beaten because most humans try to be progressive
Reply | Report Abuse | Link to thisMany man made and natural plagues have ravaged this world; and those who are left standing are the ones who were meant to be...even after the pilgrams voyage the children were the only strong ones to lead..HIV is just a disease and it will be replace by one more seriouse than it* How can we say one race will supperceed another...How long has mankind been trying to erase each other...now the this world is small er will all be erased and no one will be able to tell what happend how it happened or when it happened ....WHY ? the answer is ; because no one will be here to write the History of the great extection of the animal that walked on two legs that feed the world with knowledge and used machanical angles in space to talk to one another. Nobody but Dirty Illiterate two legged creatures that resemble the being that walked on two legged that feed the world food and knowledge.
Reply | Report Abuse | Link to thisTwo points of clarity -
Reply | Report Abuse | Link to thisMicrobicides are being developed for use by both men and women, to be applied vaginally or rectally.
It is a stretch to say that the majority of the transmission in Africa is heterosexual --- many countries in fact do not even report data on gay men and other men who have sex with men.
everybody is having sex so anybody can get it so wake up and use the modern medicine that was created for a disease created by modern means; I live smart people and I hope they can pull this one off and sell it to everybody or give it like a polio prevention.
Reply | Report Abuse | Link to thisFresno, California should be the place to use this drug in fact the State Prisons have need of this... Our Highs Shcools here have a high percentage of youth infected with HIV; maybe the schools can have this type of information as a Class for future Scientist of America, class for those who are interested in Medicine.
Reply | Report Abuse | Link to thisWe leave our children in the dark too long and when they need answers it's because they already have the problem...We can not stop behavior but we can sure make smart choices if we have a little more knowledge*
I wonder is this a racial thing**** I hope not. Saving a life could be your own life.
Reply | Report Abuse | Link to thisIgnorace is like this HIV it is a choice is most cases, like Education is...Are we burning books again...I do hope the studies will be revived for the hope of all living beings than reside on Planet Earth.
The well known story of, "Noahs Ark" if you ever read it... nobody jumped off the boat and it must have gotten pretty sticky but in the end they all arived safe and lived to tell the story* animals and all. Maybe not the wookpecker* but they all got ashore...this thing is bigger than we are and we need to stay in the boat together and work on it together. We maybe be asking ourselves; "what ever happend to whats his name or her name"
There are many natural ways to rid your body of HIV. In contrast with the traditional antiviral cocktails of medicine today, which cost thousands, have severe side effects, and comes with the double edged sword delema,meaning if the virus doesn’t kill you the cocktails will, this medicine is all natural.Please visit this site for the full information about this subject……http://pushgood-nomorehiv.blogspot.com/
Reply | Report Abuse | Link to thisThere are many natural ways to rid your body of HIV. In contrast with the traditional antiviral cocktails of medicine today, which cost thousands, have severe side effects, and comes with the double edged sword delema,meaning if the virus doesn’t kill you the cocktails will, this medicine is all natural.Please visit this site for the full information about this subject……http://pushgood-nomorehiv.blogspot.com/
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