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.