This is a prospective single-arm open-labeled cohort study on dialysis patients of the conversion from Aranesp® to NESP® for the treatment of anemia. The primary outcome of the study is the haemoglobin level after conversion to NESP® after 6 months. Secondary outcomes include the variability in haemoglobin level, average weekly dose of erythropoietin, safety profile of NESP®, patients' subjective assessment of fatigue and injection pain after the conversion.

Currently in Hong Kong, Aranesp®, manufactured by Amgen® is the only available Darbepoetin alpha licensed. NESP®, a Darbepoetin alpha agent manufactured by Kirin®, will be replacing Aranesp®.It is important to evaluate the therapeutic equivalence of the two agents, and its efficacy, tolerability and safety profile in the treatment of anemia in dialysis patients. Moreover, a new maximum preparation of NESP 120® microgram will be available to replace the Aranesp® 100 microgram prefilled syringe at the same cost. This larger Darbepoetin alpha preparation may allow extension of dosing intervals. This may subsequently allow cost saving and better convenience to medical staff and patients.

The objectives of this project are:

1. To investigate the effectiveness of NESP® in the achieving a stable anemia control in chronic dialysis patients with the same dose conversion from Aranesp®

2. To investigate the effectiveness of increasing the dosing interval of NESP® (but maintaining the same total dose) in sustaining a stable anemia control in chronic dialysis patients

3. To explore the possibility of cost saving in administering a larger dose NESP® but at an extended interval

   Patients will be divided into 3 groups.

   Group A. Same dose conversion group

   • Patients on stable low dose Aranesp® (on 20mcg preparations or on 40mcg every 2 weeks or less) will be converted to the same dose of NESP®

   Group B. Attempt extension of dosing interval with higher dose of NESP® preparations

   • Patients on stable dose of Aranesp® will be converted to higher dose preparation of NESP® (40 or 120 mcg preparations) with extended dosing intervals.

   Group C. Attempt dosage saving with 120 mcg preparation

   • Patients on Aranesp® 100mcg will be switched to the NESP® 120mcg preparation with slight increase in dosing interval

Inclusion Criteria:

• Adult Chinese patients (age greater than or equal to 18)
• on long-term dialysis for at least 3 months
• on Aranesp® treatment for at least 3 months
• stable hemoglobin level within the range of 9 to12 g/dL, on the same stable dose of Aranesp® within the past 2 months.
• Minimum weekly kT/V of 1.7 for peritoneal dialysis patients and 1.2 per haemodialysis session for haemodialysis patients
• Able to give informed consent

Exclusion Criteria:

Presence of

• thalassaemia
• haematological diseases
• severe hyperparathyroidism (PTH >90 pmol/L)
• iron, vitamin B12 or folate deficiency
• uncontrolled malignancy
• active blood loss or hemolysis