A Study of Four Dosing Regimens of PROCRIT (Epoetin Alfa) in Patients With Chronic Kidney Disease. Protocol Addendum: Extension Study of Maintenance Therapy of PROCRIT (Epoetin Alfa) in Patients With Chronic Kidney Disease.

The primary objective of this study is to compare the change in hemoglobin (Hb) from study start to the end of the study between the every 2 week and the every 4 week dosing regimens in patients with anemia of chronic kidney disease (CKD) initiated on PROCRIT (epoetin alfa). Protocol Addendum: The primary objective of the open-label extension portion of this study is to evaluate if epoetin alfa 40,000 Units given under the skin every six weeks, can maintain hemoglobin within the range of 11-12 g/dL in patients with anemia of CKD.