HIV Vaccine moves into Phase I of Clinical Testing Process
Supervised by: Gilbert Mallais
The end of 2011 was abuzz with news of HIV vaccine FDA approval for testing in US/ Canada this year. This new vaccine is the first attempt at using a whole inactivated virus (of subtype B) as a preventative vaccine. Trials are to begin this month in phase I, while vaccine development itself began 10 years ago and preliminary research another ten years before that. Why does drug/ vaccine development take so long? What does phase I mean and assuming phase I is only at the start of the process, what is coming for these trials in the future?
This phase of the trial focuses on laboratory development of the active agent and testing if it works on the targets of interest. The SAV001vaccine is the first preventative vaccine that has been developed from an entire HIV virus. Why the first? Researchers were able to genetically alter the virus so it is unable to cause disease and then treated the inactivated virus with radiation and chemicals to further decrease activity. Prevention is difficult as HIV viruses continuously mutate, however, Dr. Chil-Yong Kang, the scientist behind this research, believes that using the whole virus may work based on success with other RNA viruses.
The clinical trials begin with safety trials in animals to ensure that there is no toxicity.
This vaccine is now in phase I of the drug development process. At this point, they are taking 40 healthy individuals to check its safety in humans specifically.
If the vaccine passes phase I, it will then be tested on 600 HIV- patients from the “high risk group” to check the effectiveness of the vaccine in generating an immune response. This is the hardest phase for a drug to pass through, which means that although the active agent may seem to work well in vitro (in the lab), it may not effectively work on the target in vivo (in the human).
This phase would take 6,000 HIV- volunteers which will either be vaccinated or not. These people will then be followed for the next 3 years to see how many have been infected with HIV.
Data collected in trails is then turned over to a governmental health agency, such as the FDA or Health Canada, and closely examined by their researchers. This phase may be accelerated when the therapy targets a disease that has no treatment or cure like HIV in the 1990s.
Post Market Surveillance
Phases IV/V occur once the drug is put on the market. In previous trials, rare adverse reactions to the drug were likely not yet found due to the small sample size. The drugs are constantly monitored while administered to patients and the results are sent back to the drug company.
All in all, drug and vaccine testing is a long tedious process that generally lasts about 12 years from start to finish and costs about 1 billion dollars. However, the hurdles are there for a reason: this process ensures that new treatments are safe, effective and can help a large portion of the HIV+ population. As the old adage says, good things come to those who wait…
Information on the specific HIV trial taken from: http://www.thestar.com/news/canada/article/1104653–canadian-developed-hiv-vaccine-approved-for-human-studies?bn=1