Randomized study of tenapanor added to phosphate binders for patients with refractory hyperphosphatemia

IntroductionSerum phosphorus management is important for patients with chronic kidney disease on dialysis to reduce the risk of hyperparathyroidism and ectopic vascular calcification. Phosphate binders (PBs) control serum levels, but some do not achieve adequate existing PBs. The similar mechanisms action each PB may limit their ability lower levels. Therefore, drugs novel that can be added PBs further levels are desired. Tenapanor, a selective inhibitor intestinal sodium/hydrogen exchanger 3 transporters, decreases passive phosphate absorption in intestine, thereby decreasing levels.MethodsThis study evaluated efficacy safety tenapanor treatment up-titration when among Japanese hemodialysis hyperphosphatemia poorly controlled by alone. In total, 169 taking whose level was ≥6.1 <10.0 mg/dL initiated 8-week (placebo + PB, n = 85; 84).ResultsThe least squares mean change from baseline Week 8 −0.24 −2.00 placebo groups, respectively, statistically significant difference between groups (−1.76 mg/dL; P < 0.0001). Diarrhea as treatment-emergent adverse event occurred 14.1% 63.1% respectively. All diarrhea events were mild or moderate.ConclusionTenapanor improved could previously alone, no new concerns raised.