Jump to content

Support our Sponsors >> Thai Friendly | Pattaya News | Pattaya Unplugged | The Night Wish Group | Thailand 24/7 Forum | TPN Property | La La Land bar | NEW PA website | Subscribe to The Pattaya News | | Pattaya Investigations | ChicaCheck | Buy/Sell Property | Isaan Lawyers | Anglo Siam Legal | Add your Text or Event here

IGNORED

Anti-HIV Pills


mudaliyar
 Share

Recommended Posts

Anti-HIV Pills Powerfully Protect Uninfected Heterosexuals

 

 

it's a bad day for the AIDS virus. Results from two studies in sub-Saharan Africa, simultaneously announced today, show for the first time that daily doses of anti-HIV pills taken by uninfected men and women can prevent heterosexual transmission of the virus. Widely hailed as a "breakthrough" in HIV prevention by public health officials, the studies—one of which dropped its placebo arm today because of the convincing effects of the intervention—add powerful new tools to derail transmission of the virus in the population that accounts for most of the 34 million infections in the world.

"The evidence we're providing today is extraordinarily strong," says Jared Baeten, an epidemiologist at the University of Washington, Seattle, who co-led the larger of the two studies. "We're thrilled." Epidemiologist Lynn Paxton, who coordinated the second study for the U.S. Centers for Disease Control and Prevention (CDC), says the word " 'exciting' is a low-key term for this."

The thrill and excitement were shared around the world as select HIV/AIDS researchers over the past 2 days received confidential briefings about the results from the two pre-exposure prophylaxis (PrEP) studies. "I'm as happy as a guy could be," says Robert Grant, a virologist at the University of California, San Francisco (UCSF), and head of a large study that reported in November a PrEP success in men who have sex with men (MSM). "We have many new opportunities to stop HIV transmission." Salim Karim, an epidemiologist at the University of KwaZulu-Natal in Durban, South Africa, who co-ran a vaginal microbicide study that showed in July 2010 the first positive results with PrEP, said these "amazing results" are "set to revolutionize HIV prevention."

CDC and University of Washington coordinated the release of their results today because on 10 July, Baeten and his co-workers, who run a study called Partners PrEP, received a surprise. To prevent bias, researchers are blinded from trial results until it ends, but an independent board occasionally peeks at the data to monitor safety and effects. The board recommended that the study abandon its placebo arm and now offer treatment to all uninfected participants.

Partners PrEP began in July 2008 and enrolled 4758 "discordant" couples in Kenya and Uganda that at the start had only one HIV-infected partner. The uninfected partners randomly received a placebo or a pill that contained a licensed anti-HIV drug: either tenofovir or a combination of tenofovir and emtricitabine known as Truvada. The infected partners, by their own country's standards, had not suffered enough immune damage to qualify for free treatment with antiretroviral (ARV) drugs; in May, a separate study of discordant couples found that treating the infected partner in a discordant couple decreased the risk of transmission by 96%. Partners PrEP provided every couple free condoms, counseling, and treatment for other sexually transmitted infections.

As of 31 May, 78 people had become infected with HIV. Of these, 47 were in the placebo group, 18 took tenofovir alone, and 13 received Truvada. So tenofovir reduced infections by 62%, Truvada by 73%. The results had high statistical significance, and Baeten said both drugs worked "comparably" in uninfected men and women, although he would not specify the number of infections by gender in different arms of the study. No serious side effects occurred.

The robust efficacy raises intriguing questions about earlier PrEP studies. The Truvada trial in MSM, completed in November 2010, had a more modest efficacy of 44%. The vaginal tenofovir gel, reported 1 year ago, protected only 39% of women. A study of Truvada in sub-Saharan African women at high risk of HIV infection, FEM-PrEP, in April ended early because no difference existed between participants receiving the pills or placebos. "Adherence is the most likely explanation for the differences," says Timothy Mastro of FHI 360, the group in Durham, North Carolina, that ran the FEM-PrEP study.

An "adherent" participant takes all medication as instructed by researchers. But often, people in the earlier clinical trials did not take their pills or insert the vaginal gels. The antiretroviral drugs, of course, can only work if they are in the blood or tissues when HIV attempts to establish an infection, so nonadherent participants who are in treatment arms of these studies make it exceedingly difficult to tease out whether infections occurred because of the drug failure or their own behavior. In the MSM trial, a sub-study of people's blood who received Truvada showed that if they had detectable levels of the drug, it reduced their risk of infection by 92%—more than double what was found in the study as a whole.

Partners PrEP plans to do studies of drug levels in blood but calculated that adherence was 97% by monitoring how many pills participants had at the end of each month. More than 95% of the participants also stayed in the study. "Our participants were extraordinarily committed to the study," Baeten says. "Being in a known, discordant partnership really motivates people to reduce their HIV risk." None of the other PrEP studies recruited discordant couples.

CDC's new PrEP data come from a trial dubbed TDF2. The 6-year study found that Truvada reduced the risk of heterosexual sex transmitting HIV by 63%. TDF2 recruited 1219 men and women in Botswana who were not coupled to each other. The dropout rate was about 20%, which complicated the analysis of the results. "In Botswana, we have an incredibly mobile population, and the study went on for a long time," CDC's Paxton says. This primary analysis included people who formally left the trial for extended periods and had no known access to Truvada, which accounted for 10 of 33 infections documented. Eliminating these 10 people, who were evenly divided between placebo and treated groups, showed that efficacy increased to nearly 78%. (CDC planned to reveal the findings next week at an international AIDS conference in Rome but went public earlier to coordinate with Partners PrEP.)

The heartening new PrEP data raise several complex issues. Researchers leading a large, ongoing study in women called VOICE that compares PrEP with pills to a vaginal microbicide plan to revaluate the ethics of continuing to use a placebo control group given the new evidence of oral Truvada's powerful impact. Sharon Hillier, a reproductive infectious disease specialist at the University of Pittsburgh in Pennsylvania, who heads VOICE, stresses that the field still needs a clearer idea of why FEM-PrEP did not work. "We need to understand much better what's going on before we say we know what's going on," Hillier says. "It drives me crazy—people have such certitude about this. It's super interesting, and we're really excited about the new results, but we need a lot more information and to talk with our stakeholders about how we weigh this body of data."

Aside from altering the design of clinical trials, the new data raise difficult financial questions. Truvada now is licensed only as an HIV treatment. If regulators change the drug's label to indicate that it works as a preventive, this could prove critical to whether insurers and governments will pay for Truvada PrEP, which at a discounted rate still costs more than $100 a year when used daily. But the world cannot now afford to treat all the already-infected people who need antiretrovirals, raising the dilemma of where scarce funds should go, to prevention or treatment. Further complicating matters, treatment makes infected people less infectious and is a form of prevention itself; next week, the World Health Organization is expected to recommend that all infected people in discordant couples receive ARVs—a huge challenge for many resource-limited countries.

UCSF's Grant stresses that people need many options to prevent transmission of HIV and that all of these advances that research has provided during the past year must be put into action. "We need more resources devoted to the war on HIV," Grant says. "The amount of money needed is small compared to other security and safety issues. This is now a fight that we can win, and we should do what it takes."

Edited by anakin
Link to comment
Share on other sites

And it is a good news?

As cynical as it is, HIV/AIDS slows down the world population growth. We are just approaching 7 billions people on the planet growing 150 per minute. I'm not sure it's in western society best interest to spend billions to increase this rate even more to 156 per minute.

Looking for Czech BM to meet in LOS in February 2012

Link to comment
Share on other sites

hiv slows down world population ?

 

where you get this kind of theory just 4.8% die because of hiv and other std 0.32% people in 100000 deaths.

 

http://en.wikipedia....f_death_by_rate

 

It's 3 million deaths a year.

Significance of this compared to other death causes is perfectly real-time displayed here:

http://www.peterruss.../WorldClock.php

Edited by danny42

Looking for Czech BM to meet in LOS in February 2012

Link to comment
Share on other sites

Note: We already passed the 7 billion population threshold.

Link to comment
Share on other sites

And it is a good news?

As cynical as it is, HIV/AIDS slows down the world population growth. We are just approaching 7 billions people on the planet growing 150 per minute. I'm not sure it's in western society best interest to spend billions to increase this rate even more to 156 per minute.

I'm having a tough time digesting this perspective. Surely there are more humane approaches to controlling population growth than through disease, war, famine? How about birth control?
Link to comment
Share on other sites

I'm having a tough time digesting this perspective. Surely there are more humane approaches to controlling population growth than through disease, war, famine? How about birth control?

 

birth control is merley a choice whilst if it was to be forced i.e every male had a vasectomy at an early age then had to apply to have the vasectomy undone when he could prove that he was capable of raising a family (funds, savings, marriage, employment e.t.c) but then moral and ethics come into play as to why should someone judge wheter or not they are capable of raising a family.

 

as danny said maybe it is natures way of trying to prevent world famine/ecological disaster/wars either way the next few hundred years will be intresting.

Link to comment
Share on other sites

thank goodness, all the people of the world will be happier if we elect republicans which will make abortions illegal and alot of the contraceptives illegal also, so we can get to 8 billion people even quicker. :rolleyes:

Edited by cariden
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share



  • COVID-19

    Any posts or topics which the moderation team deems to be rumours/speculatiom, conspiracy theory, scaremongering, deliberately misleading or has been posted to deliberately distort information will be removed - as will BMs repeatedly doing so. Existing rules also apply.

  • Advertise on Pattaya Addicts
  • Recently Browsing

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.