Recombinant human erythropoietin: has treatment reached its full potential?

For more than 15 years recombinant human erythropoietin (r-HuEPO) has been used for the treatment of renal anemia benefiting patients with improved quality of life and reduced need for blood transfusions. It is still early in the history of r-HuEPO treatment; therapy has changed little and there have been few investigations into whether current treatment strategies are optimal. Of note, current therapy makes little attempt to mimic normal erythropoietin biology. Large doses of drug are administered episodically resulting in great fluxes in serum erythropoietin levels. It is unlikely that this approach is very efficient from the erythropoietic standpoint. Furthermore the effects of these nonbiologic kinetics on extraerythroid organs that express erythropoietin receptors are unknown. In this review the current state of r-HuEPO treatment is compared to the normal biology of erythropoietin and potential pitfalls caused by divergences are explored.