Protocol Addendum: An Open-Label Extension of PROCRIT (Epoetin alfa) Maintenance Therapy Administered Every Six Weeks (Q6W) for the Treatment of Anemia of Chronic Kidney Disease (CKD). The Main Protocol, as described above, was designed to evaluate whether patients with anemia of CKD could be started on epoetin alfa therapy at one of four dosing regimens: 10,000 U once every week, 20,000 U every two weeks, 20,000 U every 4 weeks, or 40,000 U every four weeks. As an addendum to the Main Protocol, up to sixty (60) patients completing the original protocol with a hemoglobin (Hb) between 11 and 12 g/dL will be given an opportunity to enroll in an open-label extension study that will begin at the end of the Main Protocol timeline (Week 17). The primary objective of this open-label extension is to evaluate if epoetin alfa 40,000 U given SC every six weeks (Q6W), can maintain Hb within the range of 11-12 g/dL in patients with anemia of chronic kidney disease (CKD).