2026 Volume 59 Issue 1 Pages 1-6
Tenapanor selectively inhibits the passive paracellular transfer of phosphate in the intestinal tract, thereby reducing serum phosphate levels. This novel mechanism of action may contribute to improved phosphate management. The present study was aimed to assess the efficacy of add‒on tenapanor therapy to reduce serum phosphorus in hemodialysis patients with secondary hyperparathyroidism taking phosphate binders, including 98 patients whose serum phosphorus level＞6.0 mg/dL. The observation period was 24 weeks from the initiation of tenapanor. Achievement of target phosphorus＜6.0 mg/dL and adverse effects (AEs) were recorded. The mean serum phosphorus level decreased from 7.1 mg/dL on day 1 to 5.0 mg/dL after 24 weeks of administering tenapanor. In patients receiving tenapanor, the mean (standard deviation) change in the serum phosphorus level after 24 weeks was －1.86 (1.68) mg/dL. The target phosphorus level was achieved in 61 patients. Diarrhea was the most common drug‒related AE, and it occurred in most patients in the tenapanor groups. Other AEs were observed with add‒on tenapanor or phosphate binders. Therapy with existing phosphate binders and add‒on tenapanor resulted in a significant decrease in serum phosphorus levels of patients with refractory hyperphosphatemia despite treatment with phosphate binders. No new safety signals were noted, and add‒on tenapanor was generally well tolerated.
