I've had 3 kidney cats, but none of them ever ended up with anemia. I do realize though, that's it's fairly common with kidney cats. Here is the page within the above wetsite that not only discuss Anemia, but discusses treatments, including Epigen: http://www.felinecrf.org/anaemia.htm
Let us know if you specific questions about it once you've looked it over. Is there some reason why you don't want to follow your Vet's advice?