Affymax ($AFFY) has banked a $50 million check from its partner Takeda Pharmaceutical after they won FDA approval for peginesatide, an anemia treatment that will now compete with Amgen ($AMGN) for market share. The biotech will co-promote the treatment in the U.S., which will be sold as Omontys. Analysts expect it to earn upward of $700 million a year, much of it taken from Amgen's Epogen franchise. Release