The advent of
erythropoiesis-stimulating agents (ESAs) such as recombinant human
erythropoietin (rHuEPO) and
darbepoetin alfa for the treatment of
chemotherapy-induced anaemia was associated with decreased requirements for red blood cell (RBC) transfusions and improved quality of life in
cancer patients. Dosing of rHuEPO three times per week is the originally approved regimen, although in some countries weekly dosing is approved in some settings.
Darbepoetin alfa was the first ESA to be developed with an extended dosing interval, offering the potential for less frequent administration and greater convenience for patients and healthcare professionals. In a placebo-controlled study of once-weekly
darbepoetin alfa treatment in anaemic
cancer patients undergoing
chemotherapy, significantly fewer treated patients required RBC transfusions, regardless of initial haemoglobin levels. A subsequent dose-finding study of once-every-3-week
darbepoetin alfa treatment showed that the
drug was effective and well-tolerated in anaemic
cancer patients and reduced the need for transfusions at all doses compared with placebo. Timing of ESA administration may be crucial to achieve maximum erythropoietic responses, thus synchronous dosing with 3-weekly
chemotherapy cycles may improve efficacy and convenience. Recent trials have shown that synchronous dosing is equally effective, with improved convenience, compared with asynchronous dosing, and that fixed-dose (500 microg) treatment achieves similar efficacy and tolerability as administration by weight.