Currently, therapy with phosphate binders is recommended to correct hyperphosphatemia; prospective, randomized long-term trials need to be conducted in patients with CKD stages 2 to 4 to evaluate whether phosphate binders could lead to a sustained reductions in serum FGF-23 levels and whether such reductions would prolong kidney and patient survival and prevent the development of secondary hyperparathyroidism, as predicted by earlier studies. This evidence concerns the gene FGF23 and secondary hyperparathyroidism.