Efficacy and Safety of SBR759, a Novel Calcium-free, Iron(III)-based Phosphate Binder, in Asian Patients Undergoing Hemodialysis: A 12-week, Randomized, Open-label, Dose-titration Study Versus Sevelamer Hydrochloride

Aim: SBR759 is a calcium-free, polymeric, iron(III)-based oral phosphate binder, in development for the treatment of hyperphosphatemia. The efficacy and safety of SBR759 was compared with sevelamer hydrochloride in chronic kidney dialysis patients on hemodialysis.

Methods: Japanese and Taiwanese hyperphosphatemic patients who were on hemodialysis (n = 203) received starting doses of 3.0 or 4.5 g/day SBR759 or 2.4 or 4.8 g/day sevelamer-hydrochloride (HCl) based on baseline phosphate levels. Daily doses were up-titrated every 2 weeks to reach the Kidney Disease Outcomes Quality Initiative (K/DOQI) recommended target serum phosphate concentration ≤1.7 mmol/L. The key endpoints were proportion of patients achieving target serum phosphate and the safety at week 12.

Results: SBR759 showed a superior phosphate response at week 12 compared with sevelamer-HCl (83% vs 54% patients; P < 0.0001). Mean serum calcium concentrations were unaffected by either treatment. Similar incidences of adverse events and serious adverse events were seen with SBR759 and sevelamer-HCl (90.3% vs 94.1% and 5.2% vs 4.4%, respectively), but overall discontinuation rates were lower with SBR759 (11.9% vs 20.6%). The proportion of patients experiencing gastrointestinal disorders was lower in SBR759 versus sevelamer-HCl. No treatment-related serious adverse events were reported.

Conclusions: SBR759 showed superior phosphate control with a favorable tolerability profile compared to sevelamer-HCl in hemodialysis patients.