iFGF23 and cFGF23 levels over time. (A) Mean iFGF23 levels, (B) LS mean percentage change from baseline in iFGF23 levels, (C) mean cFGF23 levels and (D) LS mean percentage change from baseline in cFGF23 levels. *p = 0.0102; **p < 0.05 vs placebo. Statistical significance was assessed using analysis of covariance. Lanthanum carbonate, n = 17; placebo n = 12. For cFGF23 (c and d) one patient was missing from the placebo group at week 1. (A) and (C) show mean values ± standard deviation; (B) and (D) show LS mean ± standard error. cFGF23, C-terminal fibroblast growth factor 23; iFGF23, intact fibroblast growth factor 23; LS, least-squares.