Use of darbepoetin alfa (Aranesp) in pediatric kidney disease

Objectives: Darbepoetin alfa (Aranesp®) is a novel erythropoiesis stimulating protein that has beenshown in adult trials to have safety and tolerability equivalent to recombinant human erythropoietin.However, to date there is only limited published data on the use of Aranesp inpaediatric patients.The objective of this study was to determine the safety and efficacy of darbepoetin in children withchronic and endstage kidney disease.Methods: From 2003 to 2006, 30 children with either chronic or end stage kidney disease wereenrolled in a prospective observational study. The initialdose of darbepoetin was 0.45 mcg/kgweekly (either IV or SC) and subsequent dose was titrated to achieve haemoglobin (Hb) between110 and 130 g/dl.Results: Data analysis to date includes 22 patients (16 male : 6 female) whose agesranged from 1month to 17 years (mean 9 years). Hb improved significantly with darbepoetin treatment from mean84 g/dl (range 64-107) at start of treatment to 115 g/dl (range 81-147, p<0.001) at completion. Themean starting dose was 0.55 mcg/kg/week (range 0.4-0.9) which was not significantly different tothe dose atthe end of the study (0.57 mc/kg/week, range 0.5-2.5). However, there was a significantchange in the frequency of administration, with 85% commencing on weekly treatment, but only25% still on weekly treatment at the end of the study (p<0.001). The most common treatmentinterval in stable patients was fortnightly (40%) but a significant number tolerated even longerintervals (25% dosed every 3 weeks or longer). Injection pain was common, but there were no othersignificant adverse events.Conclusions: Darbepoetin alfa is a safe and effective therapy for anaemia associated with kidneydisease. The majority of children will maintain satisfactory haemoglobin at a dosing interval ofevery 2 weeks orgreater.