Thursday, November 8, 2007

The AIDS vaccine. Why it failed and where to go from here

Hey all, this was an interesting overview of what went wrong with the AIDS vaccine trials that stopped in October. Apparently one of the theories is that because the vaccine was using an adenovirus shell with some HIV genes inside, the human immune response was too competent at recognizing and eliminating the adenovirus. In fact they apparently found that highest rates of HIV were found in people that had very high immunity to the common cold (usually an adenovirus). So where do they look now? Unfortunately, many of the other up and coming vaccines are based off of very similar technology as the failed Merck vaccine. A shift may be coming towards a live-attenuated vaccine, or others may try a different viral vector. It has been proposed that the chickenpox virus (a herpes virus) may in fact be a better vector. But that makes me a little skeptical, seeing as how many people already have strong immunity to the chickenpox... Other ideas are direct injections of HIV DNA fragments, which I guess must be cDNA rather than the actual RNA... Anyway, that's the update, I think it makes a lot more sense having spent time learning about vaccines this week. Here's the full article at the bottom.


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