A Clinical Research study performed in conjunction with Volunteer Medical Research and Coastal Nephrology Associates of Port Charlotte, FL.

Study Overview

Study Title

A 26-Week, Phase 3, Open Label Study with a 12-Week, Placebo-Controlled, Randomized Withdrawal Period Followed by an Open Label Long Term Safety Extension to Evaluate the Safety and Efficacy of Tenapanor to Treat Hyperphosphatemia in End-Stage Renal Disease Patients on Hemodialysis and Peritoneal Dialysis

Protocol No: TEN-02-301

Sponsor: Ardelyx, Inc.

Investigator: Rohit Pankhaniya MD


You are being asked to take part in a research study of an experimental drug, tenapanor, because you are taking a phosphate binder medication for your hyperphosphatemia, you have end-stage renal disease (ESRD), and you have been on hemodialysis 3 times per week for at least the past 3 months or on peritoneal dialysis for a minimum of 6 months. Tenapanor is an experimental drug being developed to reduce the amount of phosphate that enters the blood from the food you eat. “Experimental” means that tenapanor is currently being tested and has not been approved for sale in the United States by the U.S. Food and Drug Administration (FDA).

The primary purpose of this research study is to compare the phosphate lowering effect of tenapanor with placebo (a tablet that looks like the study drug but does not contain any active ingredient). The term “study drug” refers to both tenapanor and placebo in this form. The change in serum phosphorus levels will be compared from the end of the 26-week treatment period to the end of the 12-week randomized withdrawal period. During the double-blinded 12-week randomized withdrawal period, half of the subjects who are taking tenapanor will stay on their current treatment and the other half will receive placebo. A secondary goal is to show the change in serum phosphorus levels from baseline (beginning of treatment) to the end of 26 weeks of treatment period. Another secondary goal is to assess the long-term safety of tenapanor. To achieve this, there will be an active control group that will receive, an approved phosphate binder, sevelamer carbonate based on standard of care according to the instructions in its package insert. The active control group is being used to compare to tenapanor for safety purposes only. Tenapanor is minimally absorbed, which means that very little or no study drug should be found in your blood.

Payment for Participation
For your time and inconvenience related to your participation in this study, you will be paid for the study visits you complete. If you do not complete the study, for any reason, you will be paid for each study visit you do complete. You will be paid $65.00 for each completed study visit. The IRS requires subjects that receive cumulative payments of $600 or more in a calendar year to report this income on their tax returns. Our site will request that every participant complete a W-9 tax form at the same time as signing the informed consent. If your study stipends are $600 or more for the calendar year, you will receive a 1099-MISC to report on your tax return. If your stipends are less than $600 per calendar year, you will not receive a 1099-MISC.

You or your insurance company will not be charged for items or services that are provided solely for the purpose of the study, including the study drug and active control. You or your insurance company may still be charged for all routine costs including costs that are part of your usual medical care that you could have incurred regardless of your enrollment in this study.


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