A 4-Week Dose-Ranging and Efficacy Trial of KRX-0502 (Ferric Citrate) in Patients With End-Stage Renal Disease
Condition: Hyperphosphatemia; End-Stage Renal Disease
MeSH terms: Kidney Diseases; Kidney Failure, Chronic; Hyperphosphatemia
Intervention: ferric citrate
Intervention description: 1, 6, or 8 g/day taken within 1 hour of meals or snacks daily for 28 days
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 154.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Hyperphosphatemia; ESRD; Dialysis; End Stage Renal Disease; Phosphorus; Renal; Kidney

Summary:

      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.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Males or non-pregnant, non-lactating females

          -  Age > 18 years

          -  On thrice weekly hemodialysis or peritoneal dialysis for at least the previous three
             months prior to Screening Visit (Visit 0)

          -  Serum phosphorus levels ≥ 3.5 mg/dL and < 8.0 mg/dL at Screening Visit (Visit 0)

          -  Serum phosphorus levels > 6.0 mg/dL during the washout period (Visits 2 or 3)

          -  Taking 3 to 15 tablets/capsules per day of 667mg calcium acetate or 800 mg sevelamer
             (hydrochloride or carbonate), or any combination of these agents as reported by the
             patient at Screening Visit (Visit 0)

          -  Serum ferritin <1000micrograms/L and Transferrin Saturation (TSAT) <50% at the
             Screening Visit (Visit 0)

          -  Willingness to be discontinued from current phosphate binder(s) and initiated on
             KRX-0502 (ferric citrate)

          -  Willing and able to give informed consent

          -  Willing and able to stay on a constant dose of Vitamin D (or its analogs) and Sensipar
             (cinacalcet) for the treatment period, if applicable.

        Exclusion Criteria:

          -  Parathyroidectomy within six months prior to Screening Visit (Visit 0)

          -  Actively symptomatic gastrointestinal bleeding or inflammatory bowel disease

          -  Serum phosphorus levels >10.0 mg/dL documented in all of the three monthly
             laboratories (done routinely in the dialysis unit) in the three months prior to the
             Screening Visit (Visit 0)

          -  History of multiple drug allergies or intolerances

          -  History of malignancy in the last five years (treated cervical or non-melanomatous
             skin cancer may be permitted if approved by CCC)

          -  Previous intolerance to oral ferric citrate

          -  Absolute requirement for oral iron therapy

          -  Absolute requirement for Vitamin C (multivitamins [Nephrocaps, Renaphro, etc.]
             allowed)

          -  Absolute requirement for calcium-, magnesium-, or aluminum-containing drugs with meals

          -  Psychiatric disorder that interferes with the patient's ability to comply with the
             study protocol

          -  Inability to tolerate oral drug intake

          -  Planned surgery or hospitalization during the trial (scheduled outpatient access
             surgery allowed)

          -  Any other medical condition that renders the patient unable to or unlikely to complete
             the trial or that would interfere with optimal participation in the trial or produce
             significant risk to the patient

          -  Receipt of any investigational drug within 30 days of Screening Visit (Visit 0)

          -  Inability to cooperate with study personnel or history of noncompliance

          -  Unsuitable for this trial per Principal Investigator's clinical judgment