Managing Hyperphosphatemia in Patients on Hemodialysis: A Comparison of Sucroferric Oxyhydroxide (SO) Monotherapy and Tenapanor with Other Non-SO Phosphate Binders

Background: The pharmacological treatment options for managing hyperphosphatemia among dialysis patients (pts) have expanded. To examine the real-world experience with phosphate binders (PB) and phosphate absorption inhibitors, we examined serum phosphorus (sP) levels and pill burden amongst pts who switched to sucroferric oxyhydroxide (SO) monotherapy or added tenapanor (TN) to non-SO PB. Methods: Adult Fresenius Kidney Care hemodialysis (HD) pts who switched from non-SO monotherapy at baseline to either (1) SO monotherapy (SO group) or (2) add-on TN to the baseline PB (+TN group) during 11/2023 -12/2023 were included. Eligible pts had sP the month before (-1M) and 3 months after switch (Q1; M1 to M3). To ensure comparability of baseline sP, we restricted analysis to pts with sP at -1M >7 mg/dL. PB pill burden and sP during the study period were described. General linear models were used to examine differences in sP between the two groups at M3. Results: On average, pts in the SO group (n=262) were 56 years old with HD vintage of 49 months, while pts in the +TN group (n=63) were 51 years with vintage of 80 months. SO pts were more likely to dialyze with a catheter (23%) compared to +TN pts (11%). The reductions in sP from -1M to M3 were comparable in both groups (diff=1.25 mg/dL in the SO group and diff=1.23 mg/dL in the +TN group), however, SO group had lower pill burden (4.3 pills in SO vs 9.8 pills in the +TN group at M3). Results from univariate and adjusted linear models (controlling for age, vintage and catheter use) showed that there were no statistically significant differences in sP at M3 between the two groups. Conclusion: For HD pts who had sP > 7 mg/dL despite treatment with non-SO monotherapy, switching to SO monotherapy or adding TN resulted in comparable reductions in sP. However, pts with SO monotherapy had less than half the PB pill burden, compared to those adding TN. Funding: Commercial Support - Fresenius Medical Care