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A Safety and Tolerability Study of Zerenex (Ferric Citrate) in Patients With End-Stage Renal Disease (ESRD)

A Safety and Tolerability Study of Zerenex (Ferric Citrate) in Patients With End-Stage Renal Disease (ESRD)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00648167
Enrollment
55
Registered
2008-04-01
Start date
2008-03-31
Completion date
2009-01-31
Last updated
2017-04-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

End-stage Renal Disease, Hyperphosphatemia

Keywords

ESRD, end-stage renal disease, end stage renal disease, hemodialysis, dialysis, kidney failure, renal failure, kidney, renal, phosphate binder, phosphorus

Brief summary

This study is to evaluates the safety and tolerability of Zerenex™ (ferric citrate) as a treatment for hyperphosphatemia in patients with End-Stage Renal Disease.

Detailed description

The purpose of this study is to evaluate the safety and tolerability of Zerenex™ (ferric citrate) as a treatment for hyperphosphatemia in patients with End-Stage Renal Disease. These patients will be switched to Zerenex™ from their current high dose of phosphate binder and, based on their serum phosphorus levels, will be titrated up from 3.4g/day of Zerenex™ to maximum tolerated and safe doses of Zerenex™. Doses will be adjusted weekly, based on serum phosphorus levels, with the maximum dose administered being approximately 12g/day.

Interventions

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.

Sponsors

Collaborative Study Group (CSG)
CollaboratorNETWORK
Keryx Biopharmaceuticals
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
19 Years to No maximum
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

Design outcomes

Primary

MeasureTime frame
The Difference in Serum Phosphorus Between Baseline (Day 0) and End of Treatment (Day 28)28 days

Countries

United States

Participant flow

Participants by arm

ArmCount
KRX-0502
Subjects in this group were initiated on a dose of 4.5 g/day (34 subjects) or 6.0 g/day (21 subjects) of KRX-0502 (ferric citrate)
55
Total55

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyAdverse Event6
Overall Studyunable to swallow tablets1

Baseline characteristics

CharacteristicKRX-0502
Age, Continuous53.46 years
STANDARD_DEVIATION 11.48
Region of Enrollment
Puerto Rico
5 participants
Region of Enrollment
United States
50 participants
Sex: Female, Male
Female
23 Participants
Sex: Female, Male
Male
32 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
46 / 55
serious
Total, serious adverse events
4 / 55

Outcome results

Primary

The Difference in Serum Phosphorus Between Baseline (Day 0) and End of Treatment (Day 28)

Time frame: 28 days

ArmMeasureGroupValue (MEAN)Dispersion
KRX-0502 (Ferric Citrate)The Difference in Serum Phosphorus Between Baseline (Day 0) and End of Treatment (Day 28)Baseline5.9 mg/dLStandard Deviation 1.4
KRX-0502 (Ferric Citrate)The Difference in Serum Phosphorus Between Baseline (Day 0) and End of Treatment (Day 28)Day 285.4 mg/dLStandard Deviation 1.4

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026