They don't use EPO anymore - or at least not Procrit - that was certainly what they used to use.
EPO is naturally made in the body, but not at the high levels that they want.
Procrit was nice for a bit because they couldn't test for it, since our bodies make EPO themselves...
But nowadays they have a test for it.
As a result, it in fact stops the cyclists from using Procrit, which is the intent.