[vertis]

Yes, but immunity has many definitions, including 'to fight off'.

Since it's essentially teaching the immune system, why does this not work when the patient is already infected.

I thought there may be some difference between this and traditional vaccines as well.

[j2d3]

This story discusses other HIV vaccine efforts that are targeted at already infected and stop the dependence on the HIV meds:

http://www.livescience.com/18107-hiv-therapeutic-vaccines-pr...

according to that article there are 34 million people already infected worldwide.