gary,
Truth is, no one really knows how vaccines work. It's theory + empirical research + clinical testing that makes a vaccine. We still are not exactly sure how smallpox or polio vaccines work. That's just the way it is in an empirical science -- it is only in the last year or two that the secrets of how aspirin actually works have been elucidated.
Opponents of VaxGen claim that HIV is a disease of a part of the immune system that is not mediated by humoral antibodies (the disease affects a different set of immune system cells-- the T-cells); and they therefore doubt that a humoral-based strategy could be used to combat a T-Cell mediated disease.
That is their theory. These opponents have no idea whether or not their theory is true. They believe it is.
But VaxGen claims that it is not fighting the HIV disease, once established. It is preventing the virus from taking hold. AIDSVAX is not targeted on the end-stage immune system deformity (T-cell dysfunction); rather, it aims to prevent the establishment of the virus in the immune system.
So, to answer your question, AIDSVAX does not HAVE to work in humans given that it works in the chimp. As I said before, the simian model is a good one and the only one we have, but it is another species and we just don't know enough about how vaccines work to make that conclusion.
Second, the critics of AIDSVAX base their arguments on a theoretical point concerning immune system mechanics; a point that I feel is wrong-headed.
Most importantly, if Dr. Francis heeded those critics he would not have developed this vaccine that has now progressed to phase III and is more than likely going to be the first commercially available vaccine against HIV. If you research scientific opinion concerning the Salk polio vaccine you will see a similar scientific community debate. Salk was vilified. The vaccine was ridiculed. In truth, it wasn't a perfect vaccine. But what happened? Everyone in the vaccine universe dropped what they were doing and started working on the Salk prototype.
Think about that.
Even if VaxGen is only 30% efficacious, do you think that the rest of the research efforts in the world will spend billions of dollars and 5-10 years developing some NEW approach that may or may not work?
No. The Polio vaccine analogy will follow through. The naysayers will all drop what they are doing and work on the AIDSVAX prototype (just as Sabin's vaccine was an improvement on Salk's).
VaxGen will have the technology, the mechanics of production, the patents, and the backing of Genentech. And the world will come to us.
Regards,
GPSite |
