Two drugs, which are already used to treat HIV, have shown great promise as a vaccine in animal trials, it emerged this week. Tenofovir (Viread) and emtricitabine, or FTC (Emtriva) are usually sold in combination, and are often used by medical personnel accidentally exposed to the virus, as well as positive pregnant mothers to avoid passing on HIV to their children.
The drugs have been tested in monkeys as a vaccine, and have been so successful in preventing infection, that scientists are now expanding testing to include healthy high-risk people around the world.
The drugs don’t work as traditional vaccines, but do stop the virus from replicating itself. The tests show that by taking these drugs before exposure to HIV (the exact time frame required is not yet known) this may prevent infection.
Animal trials revealed that monkeys on the drugs, which were repeatedly exposed to the virus, did not get infected. Scientists were also pleased to note that after they stopped administering the drug, the monkeys continued to remain free of the virus.
Some HIV-negative gay men have been using the drug as a vaccine illegally. Doctors fear that uncontrolled and untested use may result in resistance to the drug by the HI Virus. Some also fear that the existence of a possible vaccine may lead to people returning to unsafe sex practices.