Phase III pivotal trial data for RDZ 5792 for hyperphosphatemia published in Journal of the American Society of Nephrology

Ardelyx announced the publication in the Journal of the American Society of Nephrology (JASN) of results from the first of two Phase III pivotal trials for RDZ 5792 (tenapanor) to treat hyperphosphatemia in patients with end-stage renal disease (ESRD) who are on dialysis. During the treatment period, 164 patients completed treatment in one of three randomized dosing groups (3, 10 and 30 mg titration) of tenapanor twice daily. The data demonstrated that there were significant decreases in serum phosphate in all three treatment groups, with mean reduction of 1.0-1.2 mg/dL over 8 weeks (all P < 0.001). Notably, in a pre-specified secondary analysis of serum phosphate changes in the randomized withdrawal period, there was a statistically significant difference in increases of serum phosphate levels between pooled patients on tenapanor and placebo (n=164; p = 0.003).

Ardelyx's second Phase III study, the PHREEDOM trial, is fully enrolled, and the company expects to report results from this registration-enabling study in the fourth quarter of this year. Ardelyx's third Phase III study, the AMPLIFY trial, designed to evaluate expanded use of tenapanor as adjunctive therapy to phosphate binders, is enrolling patients, and the company expects to report results in the second half of 2019.

See: "Efficacy and Safety of Tenapanor in Patients with Hyperphosphatemia Receiving Maintenance Hemodialysis: A Randomized Phase 3 Trial" Geoffrey A. Block et al. JASN March 2019, ASN.2018080832; DOI: https://doi.org/10.1681/ASN.2018080832