Experiments in female monkeys have for the first time shown that when used in combination, vaginal gels known as microbicides can protect against an HIV-like virus. The research, funded largely by the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health (NIH), suggests that similar combination microbicides could potentially provide a safe, effective and practical way to prevent HIV transmission to women, according to study investigators.
The study, published online October 30 in the journal Nature, represents the first successful testing of combination microbicides in a primate model.
Women make up nearly half of all people living with HIV worldwide, and a vast majority of new cases of HIV infection in women result from heterosexual intercourse. This study demonstrates that combination microbicides are feasible, says NIAID Director Anthony S. Fauci, M.D. We need to build on these promising animal studies and move toward establishing the safety and effectiveness of combination microbicides in women.
Vaginal microbicides include creams, gels or other substances that could be applied topically to prevent the transmission of HIV and other sexually transmitted infections. At least five different candidate microbicides currently are being evaluated in large clinical trials, but no microbicide has yet been approved for human use.
The Nature study was led by John P. Moore, Ph.D., of the Weill Medical College of Cornell University in New York City, and Ronald S. Veazey, D.V.M., Ph.D., of the Tulane National Primate Research Center in Covington, LA. For the experiments, they used simian-human immunodeficiency virus (SHIV), a hybrid virus made in the laboratory from HIV and its cousin, SIV, which infects only non-human primates. The researchers tested three microbicide gels alone and in combination. Two contained small molecules and the third featured a modified assembly of protein building blocks; each of the three was designed to block SHIV from entering specific cells in the vaginal area and thereby prevent the virus from invading the monkey’s body. The two small molecules were provided by Bristol Myers Squibb Inc. (BMS), based in Wallingford, CT, and Merck Research Laboratories, headquartered in Rahway, NJ. Weill Cornell Medical College supplied the third compound, which is similar to the approved anti-HIV drug Enfuvirtide (Fuzeon).
During testing, researchers sedated the monkeys, applied the experimental gels, and exposed the animals to a single virus dose 30 minutes to 12 hours later.
Each of the three microbicide gels provided protection against the virus when used alone. Moreover, of the 20 monkeys given the BMS and Merck microbicides in combination, 16 were protected from infection. All three monkeys given the triple combination of microbicides remained virus-free. None of the monkeys appeared to experience vaginal irritation or inflammation from the experimental gels. Of note, the researchers found that the Merck and BMS compounds could be applied up to six hours prior to exposure to the virus and still offer protection.
This is encouraging for the development of a microbicide for use in the real world, says Dr. Moore.
IT IS OBIVIOUS TO NOTE THE ANTI HIV ACTION OF HOMOEOPATHIC MEDICINE IS A TRUE FACT.I HAVE NOTICED A DRASTIC FALL IN HIV VIRAL LOAD IN A HIV POSITIVE PATIENT .THE VIRAL LOAD FROM 4999800 COPIES /ML HAS REDUCED TO 32000 COPIES /ML IN 27 DAYS.
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