Present and future strategies in the treatment of renal anaemia

Recombinant human erythropoietin therapy has transformed the management of renal anaemia over the last decade or so. We have learned much about the op timum regimens for using this drug, including the route of administration, dosage frequency, use of iron supplementation, and management of poor respo nse. Thus, dosage requirements of epoetin are generally lower if the drug i s administered subcutaneously, and the most commonly used dosage frequency is two or three times weekly. The vast majority of patients respond very we ll to treatment, but similar to5-10% of patients show some resistance to ep oetin, the most common cause of which is iron deficiency. The presence of i nfection or inflammation and under-dialysis are other important causes of a poor response to epoetin. There is increasing interest in treating renal a naemia at an earlier stage in the course of the disease, and there is much circumstantial evidence to support this strategy. This usually involves giv ing epoetin to pre-dialysis patients, and a study has also recently commenc ed to investigate the effects of preventing renal anaemia ever developing. Other erythropoietic substances are being developed, and the first of these to be ready for clinical use is novel erythropoiesis stimulating protein ( NESP), which is an analogue of erythropoietin containing two extra N-linked carbohydrate side-chains. Other potential erythropoietic substances are st ill at the laboratory stage of development, but may be available for therap eutic use in the next decade or so.