Effects of sucroferric oxyhydroxide and sevelamer carbonate on chronic kidney disease–mineral bone disorder parameters in dialysis patients

Abstract

Background. Treatment of hyperphosphataemia is the primary goal of chronic kidney disease–mineral and bone disorder (CKD-MBD) management. This post hoc analysis of a randomized, Phase 3 study evaluated the effects of 1-year treatment with the phosphate binders sucroferric oxyhydroxide or sevelamer carbonate (‘sevelamer’) on CKD-MBD indices among dialysis patients with hyperphosphataemia. Methods. After a 2- to 4-week washout from previous phosphate binders, 1059 patients were randomized 2:1 to sucroferric oxyhydroxide 1.0–3.0 g/day (n ¼ 710) or sevelamer 2.4–14.4 g/ day (n ¼ 349) for up to 24 weeks. Eligible patients enrolled in a 28-week extension. This post hoc analysis was performed for patients who completed ≥1 year of continuous treatment (n ¼ 549). As the treatment groups showed similar CKD-MBD outcomes, the data were pooled for this analysis. Results. Phosphate-binder therapy was associated with significant and sustained 30% reductions in serum phosphorus (P < 0.001). Median intact fibroblast growth factor-23 (FGF-23) also significantly decreased (P < 0.001) by 64% over 1 year. Intact parathyroid hormone decreased significantly after 24 weeks (P < 0.001), but levels returned to near baseline values by Week 52; minimal changes in serum calcium were observed. Of the bone resorption markers evaluated, tartrate-resistant acid phosphatase 5b (TRAP5b) decreased significantly (P < 0.001), whereas CTx increased transiently but returned to baseline levels by Week 52. The bone formation markers bone-specific alkaline phosphatase and osteocalcin both increased over 1 year of treatment. Conclusions. Overall, 1 year of sucroferric oxyhydroxide or sevelamer treatment significantly reduced serum FGF-23, which has been associated with clinical benefit in patients with CKD. The trend towards increased bone formation marker levels indicates a beneficial effect on bone metabolism.