Sucroferric Oxyhydroxide as Part of Combination Phosphate Binder Therapy among Hemodialysis Patients

Combination therapy with multiple phosphate binders is prescribed to reduce elevated serum phosphorus (sP) concentrations among patients on maintenance hemodialysis. Sucroferric oxyhydroxide (SO), an iron-based phosphate binder, has demonstrated efficacy at reducing sP while also being associated with a low pill burden. Whereas the effects of SO monotherapy have been well characterized in clinical trials and observational cohorts, little is known about the effects of SO-containing combination therapy.

Patients on hemodialysis (N=234) at Fresenius Kidney Care (FKC) who received ≥120 days of uninterrupted phosphate binder combination therapy with SO were included in this retrospective study. Patient data were censored after SO discontinuation, end of care at FKC, or completion of 12 months of follow-up. Quarterly (Q) changes in phosphate binder pill burden, mean sP, and proportion of patients achieving National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-KDOQI)-recommended sP levels (≤5.5 mg/dl) were compared between baseline (-Q1) and follow-up (Q1-Q4).

Phosphate binder combination therapy with SO was associated with significant increase in the proportion of patients with sP ≤5.5 mg/dl (from 19% at baseline to up to 40% at follow-up; P<0.001) and reduction in sP at all postbaseline time points (from 6.7 mg/dl to 6.2-6.3 mg/dl; P<0.001). Patients on calcium acetate (N=54) and sevelamer (N=94) who added SO therapy at follow-up resulted in a ≥250% increase in patients achieving sP ≤5.5 mg/dl (all P<0.001). Whereas mean phosphate binder pill burden increased with initiation of phosphate binder combination therapy with SO (15.8 pills/d at Q1 versus 12.3 pills/d at -Q1), continued use of SO was associated with down-titration of non-SO phosphate binders such that, by Q4, mean total PB pill burden reduced to 12.3 pills/d.

For patients on hemodialysis with uncontrolled hyperphosphatemia, combination therapy with SO may allow for sustained improvements in sP control without adversely affecting phosphate binder pill burden.