Study AMAG-FER-CKD-251 was a study evaluating the efficacy and safety of intravenous (IV) ferumoxytol in pediatric participants with dialysis-dependent chronic kidney disease (CKD). Study AMAG-FER-CKD-252 was a study evaluating the efficacy and safety of IV ferumoxytol in pediatric participants with nondialysis-dependent chronic kidney disease.~Due to significant challenges with enrollment for both studies, Study AMAG-FER-CKD-252 was combined with Study AMAG-FER-CKD-251 and enrollment continued under Study AMAG-FER-CKD-251.~Participants were enrolled by age cohorts in a stepwise manner following a safety review by the Data Safety Monitoring Board of 1 age cohort prior to enrollment of a subsequent age cohort, with progression from oldest to youngest: Randomization was stratified by the following age cohorts: 12 to <18 years, 6 to <12 years, 2 to <6 years, and 6 months to <2 years.~Participants who completed the combined AMAG-FER-CKD-251 and AMAG-FER-CKD-252 studies had the option of participating in this extension study.
Study AMAG-FER-CKD-253 is an extension study of the combined AMAG-FER-CKD-251 (NCT01155375) and AMAG-FER-CKD-252 (NCT01155388) studies to evaluate the efficacy and safety of episodic treatment of iron deficiency anemia (IDA) with ferumoxytol.