The Effect of Lanthanum Carbonate on Fibroblast Growth Factor 23 ( FGF23) in Chronic Kidney Disease

Randomization To either Lanthanum Carbonate 1 pill TID/Placebo 1 pill three times a day (TID) Day 15 If phosphorus is 3.5mg/dL-5.5mg/dL Continue with 1 pill TID. If phosphorus \<3.5mg/dL Reduce to 1 pill twice a day (BID). If Phosphorus \>5.5mg/dL 1 pill with breakfast 1 pill with lunch 2 pills with dinner Day 30 If phosphorus is 3.5mg/dL-5.5mg/dL Continue with 1 pill TID If phosphorus is \<3.5mg/dL Reduce to 1 pill daily. If phosphorus \>5.5mg/dL 1 pill with breakfast 2 pills with lunch 2 pills with dinner Day 45 If phosphorus is 3.5mg/dL-5.5mg/dL Continue with 1 pill TID If phosphorus \<3.5mg/dL stop the drug If phosphorus is \>5.5mg/dL 2 pills with breakfast 2 pills with lunch 2 pills with dinner

Initial dose of placebo will be 1 pill three times a day