Study to Evaluate the Safety and Tolerability of Ferric Citrate in Children With Hyperphosphatemia Related to Chronic Kidney Disease

NCT04523727 | Suspended Phase 3 FDA Drug

• 1 other identifier: KRX-0502-308
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 14

Brief Summary

This study will be conducted to assess the safety and tolerability of ferric citrate in pediatric participants with hyperphosphatemia related to chronic kidney disease (CKD).

Conditions

Hyperphosphatemia Related to Chronic Kidney Disease

Keywords

hyperphosphatemia; chronic kidney disease; CKD; ferric citrate; pediatric; dialysis

Outcome Measures

Primary Outcomes (3)

• Number of participants with serious and non-serious treatment-emergent adverse events (TEAEs) including gastrointestinal (GI) AEs of special interest

  up to Week 40

• Number of participants with clinically significant laboratory abnormalities or changes in laboratory results

  up to Week 40

• Number of participants with TEAEs leading to the discontinuation of ferric citrate

  up to Week 40

Secondary Outcomes (1)

• Change from baseline in serum phosphorus to Week 12/early termination (ET)

  Baseline; up to Week 12

Study Arms (1)

Ferric citrate

EXPERIMENTAL

Participants aged 6 to \< 17 years will receive ferric citrate for 36 weeks at a starting dose based on body weight categories.

Drug: ferric citrate

Interventions

ferric citrate DRUG

oral tablets

Also known as: KRX-0502

Ferric citrate

Eligibility Criteria

• Age: 6 Years - 16 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Age 6 years to \<17 years at Screening.
• Weight ≥ 20 kilograms (kg) (dry weight for dialysis participants) at Screening.
• Chronic kidney disease (CKD) requiring chronic dialysis (i.e., hemodialysis or peritoneal dialysis), or CKD not on dialysis with an estimated glomerular filtration rate (eGFR) \<30 milliliters per minute (mL/min)/1.73 meters squared (m\^2) at Screening.
• Documented history of CKD-related hyperphosphatemia for at least 3 months prior to the screening visit.
• If participant is or is not on phosphate binder(s) at Visit 1, serum phosphorus must be:
• to \<13 years: \>5.8 milligrams per deciliter (mg/dL).
• to \<17 years: \>4.5 mg/dL.
• If participant is on phosphate binder(s) at Visit 1, and serum phosphorus is not greater than the above stated age-limit criteria, approximately 1 to 4-weeks of washout period is required and at Visit 1a or Visit 1b, serum phosphorus must be greater than the age above stated age-limit criteria.
• Transferrin saturation (TSAT) \<50%.
• Serum ferritin of \<650 nanograms per milliliter (ng/mL).
• Parent/legal guardian must be willing and able to give written informed consent, and child (participant) willing and able to give age-appropriate assent according to local regulatory requirements.
• Female participants of childbearing potential, defined as post menarche and not surgically sterile, must have a negative serum pregnancy test.
• Dialysis adequacy stable on current mode of dialysis prior to screening and agree to maintain dialysis prescription for the duration of the pharmacodynamic assessment period unless changes are needed for safety. A minimum dialysis adequacy (dialysis clearance of urea-dialysis time/volume of distribution of urea \[Kt/V\]), defined by the following:
• Hemodialysis adequacy: single-pool Kt/V ≥1.2 for at least 1 hemodialysis session within 2 months.
• Peritoneal dialysis: At least 1Kt/V reading ≥1.8 within 4 months.

You may not qualify if:

• Active significant GI disorder, including overt GI bleeding or active inflammatory bowel disease.
• Liver transaminases (aspartate aminotransferase \[AST\] or alanine aminotransferase \[ALT\]) \>3× the upper limit of normal at Screening.
• Unable to swallow pills, if participant requires tube feeding, ferric citrate must be taken orally and not administered via feeding tube.
• Non-renal cause of hyperphosphatemia.
• Active drug or alcohol dependence or abuse (excluding tobacco use or medicinal marijuana) within the 12 months prior to Screening or evidence of such abuse (in the opinion of the Investigator).
• Malignancy, except for participants who have been disease-free for at least 2 years after curative therapy.
• Participants with a functioning organ transplant.
• A known allergy or intolerance to ferric citrate or any of its constituents.
• Female participants who do not agree to remain abstinent or assent to use a combination of 2 of the following highly effective birth control methods for at least 28 days before the first dose, during the study (including during dose interruptions), and for at least 30 days after the last dose:
• Barrier method of contraception: condoms (female or male) with or without a spermicidal agent, diaphragm, or cervical cap with spermicide.
• Intrauterine device (IUD).
• Hormone-based contraceptives which are associated with inhibition of ovulation.
• Females who are pregnant or breast-feeding other children. Participants who are being breastfed are eligible to participate in this study.
• Any other medical condition that, in the opinion of the Investigator, renders the participant unable to or unlikely to complete the trial or that would interfere with optimal participation in the trial or produce significant risk to the participant.
• The participant, in the opinion of the Investigator, is unable to adhere to the requirements of the study.

Sponsors & Collaborators

• Keryx Biopharmaceuticals: lead

Study Sites (14)

University of Alabama at Birmingham (UAB) - Children's of Alabama

Birmingham, Alabama, 35233, United States

Location

Phoenix Childrens Hospital

Phoenix, Arizona, 85016, United States

Location

University of California, San Francisco (UCSF) - Department of Nephrology

San Francisco, California, 94158, United States

Location

Stanford University Medical Center

Stanford, California, 94305, United States

Location

Children's Hospital Colorado

Aurora, Colorado, 80045, United States

Location

University of South Florida

Tampa, Florida, 33606, United States

Location

Johns Hopkins Hospital

Baltimore, Maryland, 21287, United States

Location

Helen DeVos Children's Hospital at Spectrum Health

Grand Rapids, Michigan, 49503, United States

Location

University of Minnesota

Minneapolis, Minnesota, 55455, United States

Location

Children's Mercy Hospital - Kansas City

Kansas City, Missouri, 64108, United States

Location

University of New Mexico

Albuquerque, New Mexico, 87110, United States

Location

Cincinnati Children's Hospital Medical Center

Cincinnati, Ohio, 45229, United States

Location

University of Utah

Salt Lake City, Utah, 84113, United States

Location

Seattle Children's Hospital

Seattle, Washington, 98105, United States

Location

MeSH Terms

Conditions

Hyperphosphatemia; Renal Insufficiency, Chronic

Interventions

ferric citrate

Condition Hierarchy (Ancestors)

Phosphorus Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Renal Insufficiency; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Chief Medical Officer

  Akebia Therapeutics Inc.

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 19, 2020
• First Posted: August 24, 2020
• Study Start: June 16, 2022
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): October 1, 2027
• Last Updated: February 17, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (14)