HIV, short for Human Immunodeficiency Virus, is a devastating pathogen that leads to a progressive decrease in the immune systems ability to fight off infections and cancers. Even though numerous leaps forward have been made over the years with the introduction of specific antiviral medication, medical management remains limited to slowing the progression of the disease, as no cure currently exists. It may be relevant to note however, that recently a case report discussed a patient in Germany who had been cured of his infection -- discussed in a previous blog.
Though there is no viable and safe cure, hope may be in sight. Earlier this month researchers from the University of Western Ontario in Canada announced that they have received permission from the U.S. FDA to begin human trials on their genetically modified whole killed virus -- similar to vaccines used against polio and influenza.
The first phase of the clinical trial will be conducted in the U.S., where the vaccine is being produced. In Phase I, 40 HIV-positive volunteers will be injected with the vaccine and will be observed to see if there are any severely negative or dangerous side effects.
If the vaccine, SAV001, is deemed safe, two more trials would follow. Phase II would encompass a population of 600 HIV-negative individuals who are at a high risk of contracting the virus because of lifestyle choices. If results are successful, the trial may progress to Phase III where a larger study population of ~6,000 high-risk volunteers will be split into 2 halves, one of which will receive the vaccine and the other will not.
Researchers would test the effectiveness of the vaccine in preventing infection after a three-year period. Human trials will begin in January at an estimated cost of $100 million for the first two phases of the trial, both of which are contingent on positive test results, according to the FDA.
The news from Canada comes on the heals of a clinical trial conducted in May by the HIV Prevention Trials Network (HPTN) which reported that antiretroviral drugs (ARVs) reduced the risk of heterosexual transmission by 96 percent. Researchers concluded ARVs provide a double benefit by treating the virus in individual patients while simultaneously cutting transmission rates. The journal Science chose the HIV study, known as HPTN 052, as the most important scientific breakthrough of 2011.
"This [HPTN 052 trial] does not mean that treating people alone will end an epidemic," said Science news correspondent Jon Cohen, who wrote about the trial for Science's Breakthrough of the Year feature. "But combined with three other major biomedical preventions that have proven their worth in large clinical studies since 2005, many researchers now believe it is possible to break the back of the epidemic in specific locales with the right package of interventions."
Before we get too caught up in all the good news it is important to remember that this is just the beginning, we have a long way to go. Still, I'm rooting for their success.
Please share your thoughts on these developments in our comments section below.
Related links:
Science: Breakthrough of the Year: HIV Treatment as Prevention
Full Text | Video | Behind the Scenes
Podcast: Science news correspondent Jon Cohen on the breakthrough of 2011