Conversion from Aranesp® to NESP® in dialysis patients-Exploration of dosing strategies and the feasibility of extending the dosing interval.

ABSTRACT

AIM: Darbepoetin alpha is available as Aranesp® and NESP®, which differ in the inactive component and maximum dose-strength of prefilled syringes. We conducted an observational cohort study to investigate optimal conversion strategies and the feasibility of extending dosing intervals with higher-dose preparations in dialysis patients converting from Aranesp® to NESP®. METHODS: Adult dialysis patients on Aranesp® with stable haemoglobin of 9-12 g/dL were converted to NESP® at the same monthly total dose according to one of three conversion regimens. Group A included patients on ≤80 mcg/month of Aranesp® who converted with dosing regimen unchanged. Group B patients converted to NESP® with extended dosing intervals using higher individual dose preparations. Group C were patients on 100 mcg Aranesp® who converted to NESP® 120 mcg with extended dosing intervals. Patients were observed for 6 months. RESULTS: Fifty patients were included. All 24 Group A patients maintained stable haemoglobin. In Group B, 10 patients (50%) maintained stable haemoglobin with extension of dosing interval from 1.04 ± 0.14 to 3.03 ± 1.28 weeks. Factors associated with success in extending dosing interval included a lower prevalence of cardiovascular disease and a higher Kt/Vurea in peritoneal dialysis patients. Four patients (80%) in Group C maintained stable haemoglobin after conversion to NESP® 120 mcg with extended dosing interval. The use of NESP® 120 mcg was well tolerated, and was associated with reduced patient-reported pain score and 38% reduction of drug cost. CONCLUSION: Dialysis patients on Aranesp® can be successfully converted to NESP® and the dosing interval can be extended successfully in a significant proportion of patients, which could reduce discomfort and drug cost.