Affymax's(OTC:AFFY) share price jumped about 5% yesterday -- and it looks like deja vu for shareholders today. The stock was up once again and contributed to Affymax's year-to-date gain of more than 275%. The company's flagship product is the FDA-approved drug Omontys, which treats anemia in patients who are on dialysis and suffering from chronic kidney disease. Affymax is marketing the drug in collaboration with Takeda Pharmaceuticals, and their main competitor in this space is biotech giant Amgen(NASDAQ:AMGN) and its drug Epogen. Amgen has a long-term agreement in place to sell Epogen to dialysis provider DaVita(NYSE:DVA) and has a non-exclusive contract with Fresenius Medical Care(NYSE:FMS). Affymax, however, is trying to gain market share through deals with Fresenius Medical Care and other dialysis providers.

In this video, health care analysts Max Macaluso and David Williamson look at Affymax's recent rise and discuss the importance of Omontys' sales to the future of this stock.

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