HIV prevention has a new ally in the form of a vaginal gel that could prevent the development and spread of the disease, if recent studies conducted with monkeys prove as effective in humans. Recent animal research suggests that a recently developed vaginal gel could provide protection for women from HIV and diminish the potential development of AIDS, even if applied several hours after exposure to the disease.
The study, which was published on March 12 in Science Translational Medicine, yielded evidence that the HIV gel protected a sample of five out of six monkey subjects from a hybrid AIDS virus, that is composed of simian-human DNA, when the gel was applied within a three-hour window after exposure to the AIDS-causing virus. Moreover, the same gel also protected two out of three monkeys when applied a half hour before exposure to the disease. During the study, the monkeys were treated with a gel that contains raltegravir, which is an anti-retroviral drug already approved by the Food and Drug Administration (FDA) for HIV treatment. Three hours prior to inserting the gel, the monkeys were exposed to the disease via vaginal swabbings of simian HIV to replicate sexual activity with an HIV-infected monkey. Additionally, in a segmented part of the study, the results yielded only one of three monkeys given a similar gel 30 minutes before exposure to the virus became infected. Moreover, one of six simians became infected despite the gel, while all the monkeys that received a placebo gel in the control group became infected.
The study’s lead author and researcher, Dr. Walid Heneine, who directs primate trials of HIV prevention methods for the Centers for Disease Control and Prevention (CDC), could not provide a clear explanation as to why two monkeys in the two parts of the study became infected. They have not been able to pinpoint an explanation at this time.
If the HIV gel that could prevent disease does move into human trials, it is expected that women will be asked to use it both before and after sexual intercourse or exposure to the disease. If the gel proves as effective in humans, it would be particularly useful in countries where women have little protection against domestic violence or rape because they could apply it in an emergency situation, after a partner fell asleep, or a clinic could administer it after a rape. Additionally, it could potentially be used for HIV prevention similar to products like Plan B or the morning-after pill for contraception if proven effective in humans. Moreover, such a gel could be extremely useful in protecting women from HIV because it can provide protection either before or after sexual activity.
Additional similar studies have recently bolstered further optimism in the area of HIV and AIDS prevention. Last week, two separate studies showed that injections of slow-release HIV drugs protected monkeys for weeks. Additionally, researchers showed successful results with two American babies born HIV-positive that have seemingly been cured by large doses of a three drug cocktail administered soon after birth.
The HIV gel, which contains a one percent solution of raltegravir (Isentress), blocks the ability of the HIV virus to integrate its DNA into the DNA of the monkey cells. Researchers have found that DNA integration is a crucial step in HIV infection but comes later in the infection process, typically more than six hours after exposure. Once the gel is applied, the HIV can no longer transmit its DNA into cells because the DNA degrades, so the cells do not become affected.
If proven effective in humans, the potential benefits of a HIV gel that could prevent the disease, and subsequently, prevent the development of the AIDS could prove revolutionary. It should be noted that not all individuals who test HIV-positive develop full-blown AIDS, especially with all the drug cocktails, prevention protocols, and advancing technology available in our modern times. An effective HIV gel could not only potentially prevent the development and spread of HIV and AIDS, it could literally save lives, and even provide researchers with a template for a possible cure to the devastating worldwide epidemic.
By Leigh Haugh