title: Combined therapy with lanthanum carbonate and calcium carbonate for hyperphosphatemia decreases serum FGF-23 level independently of calcium and PTH (COLC Study).
abstract: BACKGROUND
  Increased blood levels of fibroblast growth factor-23 (FGF-23) are associated with increased mortality. We evaluated the effect of combined therapy with lanthanum carbonate (LaC), a new phosphate binder and calcium carbonate (CaC) on serum levels of phosphate and FGF-23.
  
  
  METHODS
  This was a single-arm, open-label, multicenter study. Hemodialysis patients with a serum phosphate level >6.0 mg/dL despite CaC therapy were also given LaC for 16 weeks at a dose up to 2250 mg/day. CaC was given at a fixed dose throughout the 16-week period.
  
  
  RESULTS
  Of 42 patients enrolled, 36 completed the 16-week study. The serum phosphate level showed a significant decrease from 6.9 ± 1.4 mg/dL at week 0 to 5.5 + 1.2 mg/dL at week 16 (-20.0%, P < 0.05). The median FGF-23 level showed a significant decrease from 8250 ng/L at week 0 to 5000 ng/L at week 16 (-39.2%, P < 0.05). In contrast, corrected serum calcium and the serum parathyroid hormone level showed no significant changes. A significant positive correlation (r = 0.442, P = 0.007) was demonstrated between the percent reduction of serum FGF-23 and that of serum phosphate.
  
  
  CONCLUSIONS
  Both serum phosphate and FGF-23 levels were significantly decreased by treatment with LaC plus CaC.
authors.affiliation: Division of Nephrology and Blood Purification Medicine, Department of Medicine, Wakayama Medical University, Wakayama, Japan. taki@wakayama-med.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Shigematsu
authors.forename: Shigeo
authors.initials: S
authors.lastname: Negi
mesh_terms: D000328:Adult; D000368:Aged; D000863:Antacids / Q000627:therapeutic use; D002118:Calcium / Q000097:blood*; D002119:Calcium Carbonate / Q000627:therapeutic use*; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D054559:Hyperphosphatemia / Q000097:blood* / Q000188:drug therapy*; D007676:Kidney Failure, Chronic; D007811:Lanthanum / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood*; D011446:Prospective Studies; D006435:Renal Dialysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000863:Antacids; C000717427:FGF23 protein, human; D010281:Parathyroid Hormone; D010710:Phosphates; C119467:lanthanum carbonate; D005346:Fibroblast Growth Factors; D007811:Lanthanum; D000089703:Fibroblast Growth Factor-23; D002119:Calcium Carbonate; D002118:Calcium