Study Comparing Effects of Lanthanum Carbonate Versus Calcium Acetate Versus Dietary Phosphorus Restriction

Inclusion Criteria: * Male or female CKD patients \> 18 years old * Patients should be willing and able to provide written informed consent and HIPAA authorization to participate in study * Chronic kidney disease Stage 3 or 4 per K-DOQI Guidelines: estimated glomerular filtration rate (eGFR) of 15-60 ml/.min/1.73m2 by using modified MDRD equation. * Serum phosphorus \>4.6 mg/dl or plasma intact PTH (iPTH) level above 65 pg/ml or tubular reabsorption of phosphorus (TRP) \<80%. * A negative pregnancy test prior to enrollment in female patients, unless the patient is 2 years postmenopausal, or has had a documented tubal ligation or total hysterectomy. * Patients need to be off any phosphorus binders for 4 weeks prior to screening * Stable dose of vitamin D products for 4 weeks in patients receiving such agents. Dose changes in patients receiving stable and initiation of vitamin D products in patients previously not treated will not be permitted during study Exclusion Criteria: * Women who are pregnant, capable of becoming pregnant and not participating in an acceptable form of birth control, or who are breast feeding * Patients currently participating in a clinical trial with another investigational drug or device or who have receiving an investigational drug or device within 30 days of enrollment in this study * Major surgery within 2 month prior to enrollment in study or planned surgery while the patient is in the study, other than dialysis vascular access surgery. * Presence of coronary stents, artificial heart valves or pacemakers, and history of CABG * Patients with active infections requiring ongoing treatment * Patients who have had a malignancy (except for non-melanoma cancer of the skin) unless the patient has received curative treatment and has been disease free for \>2 years * Patient who the Investigator determines has a medical status that would preclude the patient's participation in the study * Patients on hemodialysis (HD) or peritoneal dialysis (PD) * Patients with a functional renal transplant * Patients with allergies to study drugs * Patients with serum calcium \>10.7 mg/dl.