A 4-Week Dose-Ranging and Efficacy Trial of KRX-0502 (Ferric Citrate) in Patients With End-Stage Renal Disease

This is a research study for people with high blood phosphorus levels who are on dialysis. This medical condition can cause weakening of the bones and damage other organs. This can lead to many health problems, and sometimes death. Phosphorus is in much of the food we eat, and is helpful to us in small amounts. Patients with kidney failure have trouble getting rid of the phosphorus eaten in food. Dialysis can help remove some of the phosphorus, but often patients must take a phosphate binder like PhosLo®, Renagel®, or Renvela® to bring the blood phosphorus levels back to normal. The purpose of this study is to see if KRX-0502 (ferric citrate) is safe and effective as a phosphate binder.

There will be a screening visit about 4 weeks receiving study drug. Upon qualifying for the study after the screening visit, patients will then be asked to stop taking their current phosphate binder for about 2 weeks. Then, if patients continue to qualify for the study, they will be entered in the study that lasts about 28 days. Study visits will happen every week during the patient's usual dialysis appointments. There will be a total of up to 9 visits for this study, and total participation time could last up to 8 weeks.