Study to Assess Darbepoetin Alfa Dosing for the Correction of Anemia in Pediatric Patients With Chronic Kidney Disease

The primary objectives of this study are the following: 1. To test if the proportion of participants achieving a hemoglobin value greater than or equal to 10.0 g/dL at any time point after the first dose during the study is greater than 0.8 when administered de novo darbepoetin alfa once a week (QW) for treatment of anemia in pediatric patients with chronic kidney disease receiving and not receiving dialysis, and 2. To test if the proportion of participants achieving a hemoglobin value greater than or equal to 10.0 g/dL at any time point after the first dose during the study is greater than 0.8 when administered de novo darbepoetin alfa every 2 weeks (Q2W) for treatment of anemia in pediatric patients with chronic kidney disease receiving and not receiving dialysis.