The Food and Drug Administration (FDA) approved darbepoetin alfa (Aranesp) for treatment of anemia as sociated with chronic renal failure (CRF) in patients on dialysis and patients not on dialysis (1). The manufacturer of the drug also filed an application with the FDA on September 18, 2001, to receive an indication for treatment of anemia in patients with cancer (Robert Hunter, Amgen Medical Affairs, personal communication, January 31, 2002). During development, the compound was called novel erythropoiesis stimulating protein, or NESP. Anemia is defined as a reduction in hemoglobin or a reduction in the number of circulating red blood cells (2). Anemia has been further categorized by severity by several groups, including the National Cancer Institute and the World Health Organization (Table 1).