The American Forces Information Services reports that Phase I clinical trials of potential anthrax vaccines are underway to test the safety of vaccines first developed via animal research. These represent the first vaccines entering clinical testing under new FDA rules that allow efficacy data to come from animal research where human efficacy testing would be problematic.
Researchers first isolated a protein from the anthrax bacteria that they believed would evoke an immune response. They then developed a way to manufacture a recombinant version of this antigen in a non-disease causing strain of anthrax.
U.S. Army Medical Research Institute of Infectious Diseases scientist Arthur Friedlander said,
What we did was identify it [the antigen], purify it to a very high degree and show that this protein by itself was protective in the most relevant animal model of human inhalational anthrax.
That model was in non-human primates. In light of the 9/11 terrorist attack and the series of anthrax letters, the Food and Drug Administration adopted a rule in July 2002 that allows researchers to use animal data for efficacy purposes in instances where performing clinical trials is either impossible, because a disease is very rare, or where — in the case of anthrax — efficacy testing in human beings would require exposing people to a potentially lethal agent.
According to Friedlander, the work underway with the anthrax vaccines “is the first test case of the concept of licensing a vaccine based on animal efficacy data and trying to correlate that with the human immune response.”
University of Maryland researcher Lydia Falk, who is overseeing one of the clinical trials, told the American Forces Information Service,
[With the human clinical trials] We can begin to compare the responses we see in humans to what had been observed in animals. That’s a critical part of the development of these vaccines. The more preliminary investigative work that we can do, the more it benefits the entire field. Our hope is that the information we gain will be able to add to those building blocks that would lead to an accelerated development plan.
Presumably Physicians Committee for Responsible Medicine will come out any day with a detailed explanation how all of the above vaccine investigational work could be completely replaced by computer models (but don’t hold your breath).
Source:
Anthrax vaccine moves into clinical trials. Karen Fleming-Michael, American Forces Information Service, July 9, 2003.