A Safety and Tolerability Study of Zerenex (Ferric Citrate) in Patients With End-Stage Renal Disease (ESRD)
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ClinicalTrials.gov Identifier: NCT00648167 |
Recruitment Status
:
Completed
First Posted
: April 1, 2008
Results First Posted
: October 9, 2014
Last Update Posted
: April 4, 2017
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Condition or disease | Intervention/treatment | Phase |
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Hyperphosphatemia End-stage Renal Disease | Drug: ferric citrate | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 55 participants |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Safety and Tolerability Study of Zerenex (Ferric Citrate) in Patients With End-Stage Renal Disease (ESRD) |
Study Start Date : | March 2008 |
Actual Primary Completion Date : | January 2009 |
Actual Study Completion Date : | January 2009 |
Arm | Intervention/treatment |
---|---|
Experimental: KRX-0502 (ferric citrate)
All patients will be switched from their current phosphate binder to Zerenex, and titrated to the maximum tolerated dose (up to about 12g/day) based on their serum phosphorus levels.
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Drug: ferric citrate
ferric citrate will be provided as a 375mg capsule. Dosing and frequency are dependent on patient's serum phosphorus levels. Dosing will occur over the 28-day study.
Other Name: KRX-0502
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- The Difference in Serum Phosphorus Between Baseline (Day 0) and End of Treatment (Day 28) [ Time Frame: 28 days ]

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Ages Eligible for Study: | 19 Years and older (Adult, Senior) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Males and non-pregnant, nonlactating females
- Age > 18 years
- On thrice weekly hemodialysis for at least the previous 3 months prior to randomization
- Phosphorous levels ≥3.5mg/dL at Screening Visit
- On at least 12 tablets/capsules/day of calcium acetate (667mg), calcium carbonate (500mg), lanthanum carbonate (500mg), sevelamer hydrochloride (800mg or two 400mg tablets), or any combination of these agents
- Serum ferritin <1000micrograms/L and Transferrin Saturation (TSAT) <50%
- Willing to be discontinued from current phosphate binder(s) and initiated on Zerenex
- Willing and able to give informed consent
Exclusion Criteria:
- Parathyroidectomy within 6 months prior to Screening
- Actively symptomatic GI disease such as peptic ulcer disease, gastro esophageal reflux, diverticulosis, irritable bowel syndrome (treated asymptomatic is permitted)
- History of documented inflammatory bowel disease or erosive esophagitis
- Serum Phosphorus levels >10.0 mg/dL documented in the 3 monthly laboratories (done routinely in the dialysis unit) in the 3 months prior to the Screening Visit
- History of multiple drug allergies
- History of malignancy in the last 5 years (treated cervical or 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 [Neprocaps, 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 study (scheduled outpatient access surgery allowed)
- Any other medical condition that renders the patient unable to or unlikely to complete the study or that would interfere with optimal participation in the study or produce significant risk to the patient
- Receipt of any investigational drug within 30 days of randomization
- Inability to cooperate with study personnel or history of noncompliance

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00648167
United States, Tennessee | |
Vanderbilt University Medical Center | |
Nashville, Tennessee, United States, 37232 |
Study Chair: | Julia B Lewis, MD | Collaborative Study Group at the Nephrology Clinical Trials Center, Vanderbilt University Medical Center |
Additional Information:
Responsible Party: | Keryx Biopharmaceuticals |
ClinicalTrials.gov Identifier: | NCT00648167 History of Changes |
Other Study ID Numbers: |
KRX-0502-201 |
First Posted: | April 1, 2008 Key Record Dates |
Results First Posted: | October 9, 2014 |
Last Update Posted: | April 4, 2017 |
Last Verified: | March 2017 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Keywords provided by Keryx Biopharmaceuticals:
ESRD end-stage renal disease end stage renal disease hemodialysis dialysis kidney failure |
renal failure kidney renal phosphate binder phosphorus |
Additional relevant MeSH terms:
Kidney Diseases Kidney Failure, Chronic Hyperphosphatemia Urologic Diseases Renal Insufficiency, Chronic Renal Insufficiency Phosphorus Metabolism Disorders Metabolic Diseases |
Citric Acid Ferric Compounds Anticoagulants Calcium Chelating Agents Chelating Agents Sequestering Agents Molecular Mechanisms of Pharmacological Action Hematinics |