PHREEDOM phase III study of Ibsrela meets primary endpoint in hyperphosphatemia in patients with chronic kidney disease.- Ardelyx

Ardelyx reported positive topline results from PHREEDOM, a long-term Phase III study evaluating the efficacy and safety of Ibsrela (tenapanor) as monotherapy for the treatment of hyperphosphatemia in patients with chronic kidney disease (CKD) on dialysis. In the study, patients randomized to the tenapanor arm were treated in a 26-week open-label treatment period and were then re-randomized to a 12-week double-blind, placebo-controlled randomized withdrawal period.

The PHREEDOM study met its primary endpoint demonstrating a statistically significant difference in least square (LS) mean serum phosphorus change (-1.4 mg/dL, p<0.0001), as compared to placebo. during the 26-week treatment period 77 of tenapanor-treated patients in the intent-to-treat population n="408)" had a decrease in serum phosphorus with a mean reduction from baseline of 2.0 mg dl. tenapanor is an investigational first-in-class phosphate absorption inhibitor being developed to treat hyperphosphatemia in patients with ckd on dialysis. tenapanor was generally well-tolerated.>

As anticipated due to the mechanism of action, the most common self-reported adverse event was loose stools/diarrhea at an incidence rate of 52.5%, with approximately 90% of these events judged by the investigator to be mild to moderate in nature. The majority of the events were reported within the first five days of treatment and were transient notwithstanding continued treatment with tenapanor. In the 26-week open-label treatment period, 16% of the tenapanor-treated patients discontinued treatment due to diarrhea. Additionally, during the randomized withdrawal period, only 0.8% of tenapanor-treated patients discontinued due to diarrhea. If approved, tenapanor will be the only non-binder treatment for the control of serum phosphorus in patients with CKD on dialysis.