STAAR-2 Clinical Study

To assess the effect of Aranesp on the hemoglobin (Hgb) of CRI subjects who are recombinant human erythropoietin (rHuEPO)-naïve or converting from rHuEPO therapy.

To assess the effect of Aranesp_ on the hemoglobin (Hgb) of CRI subjects who are recombinant human erythropoietin (rHuEPO)-naïve or converting from rHuEPO therapy. To assess the association between subject self-reported health-related quality of life (HRQoL) as it relates to Hgb concentration and glomerular filtration rate (GFR) in subjects who were rHuEPO-naïve prior to study enrollment. To characterize the health-related resource utilization of subjects with CRI. To characterize the subject satisfaction with Aranesp_ compared to previous rHuEPO therapy. To characterize iron treatment in subjects with CRI. To assess the safety profile of Aranesp_ therapy in subjects with CRI

Eligibility Criteria:
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