STAAR-2 Clinical Study

Inclusion Criteria: * ≥ 18 years old * diagnosis of CRI and not receiving dialysis therapy (must be predialysis) * measured or estimated (using the Cockcroft-Gault formula) creatinine clearance (CrCl) of ≤ 70 mL/min, or GFR ≤ 60 mL/min (using the MDRD formula): * Cockcroft-Gault formula: CrCl = (140 minus age in years) x (body weight in kg) serum creatinine (mg/dL) x 72.0 For women, the value will be multiplied by 0.85 * MDRD formula: GFR = 170 x \[SCr\]-0.999 x \[Age\]-0.167 x \[0.762 if subject is female\] x \[1.180 if subject is black\] x \[sun\] -0.170SAlb\]-0.318 * mean Hgb \< 11 g/dL during the screening/baseline period (if subject is not already receiving rHuEPO therapy) * for subjects currently receiving rHuEPO therapy, the subject must have: a stable rHuEPO dose for the past month; and a rHuEPO frequency of once weekly. * white blood cell and platelet counts within normal limits * serum vitamin B12 and folate levels above the lower limit of normal range * transferrin saturation (TSAT) ≥ 20% during the screening period * availability for follow-up assessments * subject must be able to comprehend and be willing to, or have legally accepted representative, give written informed consent for participation in the study Exclusion Criteria: * scheduled to initiate dialysis * uncontrolled hypertension (diastolic blood pressure \> 105 mm Hg or systolic blood pressure of \> 180 mm Hg during the screening/baseline period on two separate measurements) * clinically unstable in the judgment of the investigator (eg, subject is in the intensive care unit, immediately post-myocardial infarction, etc) * scheduled to receive a living donor kidney transplant * treatment of grand mal epilepsy within the past 6 months * moderate to severe congestive heart failure (NYHA class III or IV) * clinical evidence of severe secondary hyperparathyroidism (parathyroid hormone level \> 1500 pg/mL) * severe active chronic inflammatory process (eg, ulcerative colitis, peptic ulcer disease, rheumatoid arthritis, etc) * currently receiving antibiotic therapy for systemic infection (enrollment may be postponed until the course of antibiotics has ended) * known aspartate aminotransferase (AST) or alanine aminotransferase (ALT) greater than 3 times the upper limit of the normal range on more than one occasion within three months prior to screening * known positive HIV antibody or hepatitis B surface antigen * clinical evidence of current malignancy and/or receiving chemotherapy with the exception of basal cell or squamous cell carcinoma of the skin and cervical intraepithelial neoplasia * active bleeding or RBC transfusion within eight weeks of enrollment * androgen therapy within four weeks before enrollment * known hematologic disease (eg, sickle cell anemia, myelodysplastic syndromes, hematologic malignancy, myeloma; hemolytic anemia, etc) * any condition that is likely to affect subject compliance * currently or previously (within 30 days) enrolled in investigational device or drug trial(s) or receiving investigational agent(s) * the exception to this is if the subject was enrolled in another Aranesp™ or rHuEPO protocol * pregnant or breast feeding women (women of child-bearing potential must be using contraceptive precautions) * women planning to have a child during the study period * known hypersensitivity to the active substance or any of the excipients