Study to Evaluate the Safety and Tolerability of KRX-0502 (Ferric Citrate) in Children With Iron Deficiency Anemia Associated With Non-Dialysis Dependent Chronic Kidney Disease

A 24-Week, Open-Label, Randomized, 2-Arm Study to Evaluate the Safety and Tolerability of KRX-0502 (Ferric Citrate) in Children With Iron Deficiency Anemia Associated With Non-Dialysis Dependent Chronic Kidney Disease

This study will be conducted to evaluate the safety and tolerability of ferric citrate in pediatric participants with iron deficiency anemia (IDA) associated with non-dialysis dependent chronic kidney disease (NDD-CKD).

Study Overview

• Status: Withdrawn
• Conditions: Iron Deficiency Anemia Associated With Non-Dialysis Dependent Chronic Kidney Disease
• Intervention / Treatment: Drug: ferric citrate; Drug: standard of care

• Study Type: Interventional
• Phase: Phase 3

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 18 years (Child, Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 6 years to <18 years at Screening
• Body Weight ≥12 kilograms (kg) at Screening
• Chronic kidney disease (CKD) stage 3 to 5, not on dialysis, with estimated glomerular filtration rate (eGFR) <60 milliliters per minute (mL/min)/1.73 meters squared (m^2) utilizing the "Bedside Schwartz" equation
• Hemoglobin (Hgb) ≥8.5 and ≤11.5 grams per deciliter (g/dL) at Screening
• Transferrin saturation (TSAT) ≤25% at Screening
• Ferritin ≤200 nanograms per milliliter (ng/mL) at Screening

Exclusion Criteria:

• Serum phosphorus level at Screening:

  • 6 to <13 years: ≤4.0 milligrams per deciliter (mg/dL);
  • 13 to <18 years: ≤2.7 mg/dL
• Liver transaminases (aspartate aminotransferase [AST] and/or alanine aminotransferase [ALT]) ˃3× the upper limit of normal at Screening
• Active significant gastrointestinal (GI) disorder, including overt gastrointestinal (GI) bleeding or active inflammatory bowel disease
• Unable to swallow pills
• Anemia due to causes other than iron deficiency anemia (IDA) of CKD
• Intravenous iron therapy or blood transfusion within 4 weeks before the Screening visit
• Participants with a functioning organ transplant
• Receipt of any investigational drug within 4 weeks before Screening
• Phosphate binder use during the Screening period

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ferric citrate; Participants aged 12 to <18 years and 6 to <12 years will receive ferric citrate for 24 weeks at a starting dose based on body weight categories.	Drug: ferric citrate; oral tablets; Other Names: KRX-0502
Active Comparator: Standard of care; Participants aged 12 to <18 years and 6 to <12 years will receive standard of care treatment for 24 weeks.	Drug: standard of care; administered per the approved label and at the Investigator's discretion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Number of Participants with Serious and Non-serious Treatment-emergent Adverse Events	up to Week 28
Number of Participants with Clinically Significant Laboratory Abnormalities or Changes in Laboratory Results	up to Week 24
Number of Participants with Treatment-emergent Adverse Events Leading to the Discontinuation of Ferric Citrate	up to Week 28

Secondary Outcome Measures

Outcome Measure	Time Frame
Change from Baseline in Hemoglobin to Week 24/Early Termination Visit	Baseline; Week 24
Change from Baseline in Transferrin Saturation (TSAT) to Week 24/Early Termination Visit	Baseline; Week 24
Change from Baseline in Ferritin to Week 24/Early Termination Visit	Baseline; Week 24
Change from Baseline in Serum Phosphorus to Week 24/Early Termination Visit	Baseline; Week 24
Change from Baseline in Calcium to Week 24/Early Termination Visit	Baseline; Week 24
Change from Baseline in Bicarbonate to Week 24/Early Termination Visit	Baseline; Week 24

Collaborators and Investigators

• Sponsor: Keryx Biopharmaceuticals
• Investigators: Study Director: Chief Medical Officer, Akebia Therapeutics Inc.

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2025
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: November 24, 2020
• First Submitted That Met QC Criteria: November 24, 2020
• First Posted (Actual): December 2, 2020

Study Record Updates

• Last Update Posted (Actual): November 20, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: pediatric; dialysis; CKD; Iron Deficiency Anemia; ferric citrate; Non-Dialysis Dependent Chronic Kidney Disease
• Additional Relevant MeSH Terms: Metabolic Diseases; Hematologic Diseases; Anemia; Iron Metabolism Disorders; Anemia, Hypochromic; Nutritional and Metabolic Diseases; Hemic and Lymphatic Diseases; Iron Deficiencies; Anemia, Iron-Deficiency; Health Services Administration; Health Care Quality, Access, and Evaluation; Quality of Health Care; Quality Indicators, Health Care; Standard of Care; ferric citrate
• Other Study ID Numbers: KRX-0502-309

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No