Experimental vaccine helps protect monkeys against AIDS-like infection
January 5th, 2012
10:51 AM ET

Experimental vaccine helps protect monkeys against AIDS-like infection

The road to a vaccine to protect against HIV and AIDS has run into a lot of dead ends, but a new study in monkeys suggests a new path may have been found.  Researchers say two new experimental vaccines partially protected monkeys from an HIV like infection, reducing the likelihood of contracting the disease by 80% to 83%, compared to the placebo.  

Both studies, published online Wednesday in the journal Nature, tested several Simian Immunodeficiency Virus (SIV) vaccine regimens on 40 rhesus monkeys each.  Researchers found the vaccines provided some protection to monkeys that were exposed to an extremely virulent, hard to neutralize strain of SIV. Not only did the vaccines reduce the chance of infection, but for monkeys that became infected, it substantially reduced the amount of virus in their blood.

"This type of protection in terms of blocking acquisition of this tough virus challenge has not been seen before by any vaccine in this animal model," said Dr. Dan Barouch, associate professor of medicine at Harvard Medical School and lead study author.  "So I think there is reason to be optimistic; in fact, I think we are more optimistic than ever before about the possibility of an HIV vaccine for humans."

Barouch says SIV is very similiar to HIV and will give researchers insight and clues into how to design an HIV vaccine for humans. "Clinical trials have to be done and there's no guarantee, but the SIV model in rhesus monkeys is the best preclinical test of vaccine strategies before embarking on HIV vaccine clinical trials in humans."

The dose of the virus used in the animals studies was 100 times more infectious than what is seen in human exposure, according to Barouch.  Once vaccinated, the monkeys received multiple exposures to SIV over a certain period of time.  Eventually most of them did become infected, but the results are still promising, Barouch tells CNN.  "The data show these vaccine candidates achieved better protection in these preclinical models than some previously tested candidates and so therefore we are optimistic in moving the novel lead HIV candidates into clinical trials."

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, conducts and supports HIV vaccine studies around the world. They helped fund the research.

"What makes this paper so remarkable is that it represents the first time we've identified the likely correlates for both protection from HIV acquisition and control of viral replication," said Carl Dieffenbach, director of the NIAID Division of AIDS.  "This will have important implications for the next round of HIV vaccine clinical trials."

Researchers now plan to test a human-adapted version of one of the vaccine combinations in healthy adults here in the U.S. and internationally. Barouch says manufacturing has already begun.  “It is not possible to predict how this vaccine will perform in humans, but this study advances our understanding of AIDS pathogenesis and immunity," he says.

soundoff (26 Responses)
  1. Binky42

    AIDS first affected humans after cross-contaminated from chimps when the SIV virus mutated. Not that we have a common ancestor or anything 😉

    January 5, 2012 at 11:43 | Report abuse | Reply
  2. RationalFew

    Yes we do share a common ancestor. BY THE WAY, whats a creationist doing reading a science related story?

    January 5, 2012 at 12:09 | Report abuse | Reply
    • Leo

      Uh, I think Binky42's comment was tongue-in-cheek, and he/she is well aware that we ARE related to chimpanzees through a common ancestor.

      January 5, 2012 at 14:35 | Report abuse |
    • FearTheHype

      Great display of reading comprehension skills and an understanding of sarcasm. Not to mention completely overlooking the attached emoticon.

      January 5, 2012 at 15:05 | Report abuse |
  3. portland tony

    Does this mean I can have unprotected S*x with a primate? There is just enough genetic difference between humans and monkeys so that doesn't mean we have a cure for the scourge that is HIV or AIDS!

    January 5, 2012 at 12:11 | Report abuse | Reply
    • tyrexden

      I'd hope so, considering humans are primates.

      January 5, 2012 at 13:26 | Report abuse |
  4. Cynthia W.

    Do these tests on the worst of human criminals – not on innocent animals. They would be more accurate.

    January 5, 2012 at 12:36 | Report abuse | Reply
    • portland tony

      We tried that with different diseases in the rural south, Guatemala and who knows where else. Yes convicts were used for experimentation too. The 3rd Reich also espoused your belief.

      January 5, 2012 at 12:51 | Report abuse |
    • ling

      so agree!

      January 5, 2012 at 13:31 | Report abuse |
  5. PDC

    Always a possiability it will do more harm than good... I still admire the people that make their lives work, reseach, trying to help others.

    January 5, 2012 at 14:25 | Report abuse | Reply
    • FrankR

      They do not do it for free. They stand to make a lot of money if they find a vaccine.

      January 5, 2012 at 22:12 | Report abuse |
  6. Earl

    I was in college in 1980 when HIV began to be recognised. Its a good thing it is not very contagious, or it could have been a depopulation or extinction event. We have to be able to make a vaccine in a month, instead of 30 years.

    January 5, 2012 at 16:01 | Report abuse | Reply
    • jeff

      Wrong Earl, it would not have been an extinction event as, unlike cancer, AIDS is a disease that is entirely avoidable if blood products are properly srceened and you put your touque on before sex if your partner hasn't been tested.

      January 5, 2012 at 19:16 | Report abuse |
    • Samian

      Surely thou dost jest?

      Entire countries' populations in sub-Saharan Africa risk being wiped out because of the HIV/AIDS pandemic.

      January 5, 2012 at 23:00 | Report abuse |
  7. jelden

    interesting i jus saw the movie rise of the planet apes and its so similar because the people had a disease which was killing humans but it turns out when the monkeys get they some how become smarter and take over the human world.

    January 5, 2012 at 20:04 | Report abuse | Reply
    • Michael

      Yeah I was thinking of that but there's no such thing for brains to create it own cell like creating information.

      January 6, 2012 at 00:04 | Report abuse |
  8. Blendi

    Spelled Similar wrong (similiar)

    January 5, 2012 at 20:52 | Report abuse | Reply
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    January 6, 2012 at 01:55 | Report abuse | Reply
  10. portland tony

    @Jeff You are correct, however testing is not always possible. Nor are condoms. Think of first response personnel to a bloody accident or even hospital workers!

    January 6, 2012 at 11:52 | Report abuse | Reply
  11. drew

    Very good news for the black population

    January 6, 2012 at 20:19 | Report abuse | Reply
  12. Absynthe

    I would think people at high risk, would volunteer. No part of any society should be experimented on against their will, not even inmates/

    January 6, 2012 at 21:51 | Report abuse | Reply


    January 7, 2012 at 13:45 | Report abuse | Reply


    January 7, 2012 at 13:46 | Report abuse | Reply
  15. Dr s a zaidi

    Reports of vaccine are interesting and optimistic but it should not increase risk behaviour best vaccine is preventive steps

    January 8, 2012 at 00:58 | Report abuse | Reply
  16. raj

    pls decrease the sprdng of hiv/aids.vaccines quickly dedected and safe human lifes.all of u avardnace of hiv/aids.

    January 8, 2012 at 12:10 | Report abuse | Reply
  17. Jerald Dubon

    CTO Networks


    October 2, 2016 at 11:00 | Report abuse | Reply



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