Inclusion Criteria:

• Men and non-pregnant, non-lactating women greater than 18 years of age
• Able to given informed consent and complete scheduled visits
• History of established coronary artery disease as defined by coronary stenosis in one or more vessels greater than or equal to 70% by coronary angiography or CT angiogram OR abnormal stress test (at least medium-sized, moderate reversible defect) OR a presence of a CAD risk equivalent as defined by the NCEP ATP III as: Framingham risk score ≥ 20%, diabetes, or peripheral arterial disease(4)
• hs-CRP ≥ 2.0 mg/L
• History of stage 3 or 4 CKD defined as an eGRF by the MDRD equation of 15-60 mL/min/1.73 m2
• Low level of serum 25-hydroxyvitamin D (<30ng/mL)
• Evidence of secondary hyperparathyroidism defined as intact parathyroid hormone (iPTH) level > 70 pg/mL
• Stable dose of statin and/or other lipid lowering therapy (ie: ezetimibe, fibrates, bile acid sequestrants nicotinic acid, fish oil) for 12 weeks prior to enrollment without known plans for change to current therapy during the study period

Exclusion Criteria:

• History of myocardial infarction, stroke, or cardiac surgery within 6 months of enrollment
• History of carotid artery surgery
• Planned cardiovascular surgery or procedure, with the exception of permanent pacemaker placement, in the next 18 months.
• Use of vitamin D or calcium supplementation within the past 12 weeks with the exception of calcium containing phosphate binders and a daily multivitamin containing ≤ 400 IU of vitamin D
• Hypercalcemia (as defined by the laboratory upper limit of normal ) or hyperphosphatemia (≥ 5.5 mg/dL)
• Plan to initiate renal replacement therapy (dialysis) during the study
• History of left ventricular systolic dysfunction with an ejection fraction <50% or history of New York Heart Association functional Class II-IV congestive heart failure
• Uncontrolled blood pressure, defined as systolic blood pressure greater than 160 mmHg and diastolic blood pressure greater than 100 mm Hg at the screening visit
• Uncontrolled diabetes, defined as hemoglobin A1C ≥ 10.0
• History of any surgery within the past 3 months or known to be planned during the study period
• History of malignancy within the past 5 years with the exception of non-melanoma (ie: squamous cell or basal cell) skin cancer
• History of a known systemic or pulmonary inflammatory condition (including rheumatoid arthritis, systemic lupus erythematosus, chronic obstructive pulmonary disease, pulmonary fibrosis, sarcoidosis, Wegener's granulomatosis, Goodpasture's disease)
• History of renal or other organ transplant and/or immunosuppressed state (ie immunosuppressive therapy or condition such as HIV)
• History of any other condition, that in the opinion of the investigators renders it unsafe for the subject to be enrolled
• For woman able to become pregnant, unwillingness to use birth control
• Participation in another clinical trial