Darbepoetin alfa: a new approach to the treatment of chemotherapy-induced anaemia.

Chemotherapy-induced anaemia has important consequences on the quality of life and social function of cancer patients. The finding of erythropoietin (EPO) deficiency in these patients led to the therapeutic development of erythropoietic proteins. Darbepoetin alfa (Aranesp), Amgen Inc, Thousand Oaks, California), a new erythropoietic growth factor, has eight more sialic acids than epoetin alfa. The increased sialic acid content confers a three-fold longer half-life and allows the drug to be administered less frequently than epoetin alfa. Darbepoetin alfa affects the same early haematopoietic cells as epoetin alfa and the endogenous hormone EPO. Preclinical pharmacokinetic studies suggest that the intrinsic pharmacological properties of darbepoetin alfa are comparable to those of epoetin alfa, but that the increased sialic acid content allows for less-frequent administration with superior performance. Darbepoetin alfa has been shown to have safe clinical efficacy in a variety of tumour settings and with several types of chemotherapy.