<Part 1 Treatment Period> Week 1 to Week 24 Initial Phase (Week 1 to Week 4) : 50 IU/kg of Erythropoietin Alpha, three times a week (3 x 50 IU/kg/week) No dose adjustments will be permitted during the first 4 weeks of the study. Maintenance Phase (Week 5 to Week 24) The dose will be adjusted to maintain Hb levels between 10 and 12 g/dL.

<Part 2 Treatment Period> : Week 25 to Week 52 The dose of Erythropoietin Alpha will be adjusted to maintain hemoglobin levels between 10 and 12 g/dL as subcutaneous administration in accordance with the given dosing algorithm. The further details are the same as those for maintenance phase of Part 1 Treatment Period.

<Part 1 Treatment Period> Week 1 to Week 24 Initial Phase (Week 1 to Week 4) : 50 IU/kg of Erythropoietin Alpha, three times a week (3 x 50 IU/kg/week) No dose adjustments will be permitted during the first 4 weeks of the study. Maintenance Phase (Week 5 to Week 24) The dose will be adjusted to maintain Hb levels between 10 and 12 g/dL.

<Part 2 Treatment Period> : Week 25 to Week 52 The dose of Erythropoietin Alpha will be adjusted to maintain hemoglobin levels between 10 and 12 g/dL as subcutaneous administration in accordance with the given dosing algorithm. The further details are the same as those for maintenance phase of Part 1 Treatment Period.

• Strength : 3000 IU/0.3 mL, 5000 IU/0.5 mL, 6000IU/0.6 mL
• Formulation : Solution in PFS

The primary endpoint is the mean absolute change in Hb levels between the screening/baseline period (Week -2 to Day 1 of Week 1) and the evaluation period (Week 21 to Week 24).

Hb level at screening/baseline period is defined as the mean of the Hb measurements at screening and on Day 1 of Week 1 (prior to dosing). Hb level at evaluation period is defined as the mean of the Hb measurements at Week 21, 22, 23, and 24 (in detail, Day 1 of Week 21, Day 1 of Week 22, Day 1 of Week 23, and Day 1 of Week 24).

Any adverse events

Anti-drug antibody (ADA) response by Week 52 compared to baseline (Week -2~Week 1 (Prior to Dose))