Conditions: Hyperphosphatemia
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 219
Healthy volunteers: no

Brief summary:
This phase 3, 8-week, randomized, double-blind, parallel group, multi-center study with a 4-week, placebo-controlled, randomized withdrawal period will evaluate the efficacy, safety and tolerability of Tenapanor to treat hyperphosphatemia in end-stage renal disease patients on hemodialysis (ESRD-HD). Subjects who qualify are randomized into the study will either receive 3 mg BID, 10 mg BID, or a titration regimen of tenapanor.

Detailed description:
The study consists of a screening visit, a wash out period of up to 3 weeks, when existing phosphate lowering medication is withheld, an 8-week treatment period, in which all groups receive tenapanor, and a 4-week placebo-controlled, randomized withdrawal period, during which patients are re-randomized 1:1 to either remain on their current tenapanor treatment or placebo.

Depending on the increase in serum phosphate levels, subjects can be randomized 1,2, or 3 weeks after being taken off their phosphate lowering medication.

Arms:
arm 1: Tenapanor, 3mg BID (6mg total) arm 2: Tenapanor, 10mg BID (20mg total) arm 3: Tenapanor, patients start at 30mg BID and can down titrate weekly to 20, 15, 10, and 3mg BID, sequentially based on a GI tolerability question arm 4: Placebo

Interventions: intervention 1: Tenapanor intervention 2: Placebo
Intervention descriptions: intervention 1: None intervention 2: None

Protocol document: