Treatment Response of Injectafer vs Oral Iron to Baseline Hepcidin Levels in Patients With Iron Deficiency Anemia (IDA) Secondary to Inflammatory Bowel Disease (IBD) or Gastric Bypass

Inclusion Criteria: * Signed informed consent * Male or female subjects ≥ 18 years of age with clinical diagnosis of IDA secondary to IBD or Gastric Bypass * Screening Hemoglobin (Hb) ≤ 11g/dL * Screening Ferritin ≤ 100 ng/mL * Female subjects who are of childbearing age must have a negative pregnancy test at screening and be practicing an acceptable method of birth control during the study Exclusion Criteria: * Hypersensitivity reaction to any component of IV Injectafer or oral iron * Requires dialysis for treatment of chronic kidney disease (CKD) * During the 30 day period prior to screening has been treated with IV iron * No evidence of iron deficiency * During the 30 day period prior to screening has been treated with a red blood cell transfusion. * Any non-viral infection * Known positive hepatitis with evidence of active disease * Received an investigational drug within 30 days of screening * Active malignancy within 5 years. Basal or squamous cell skin cancer is not exclusionary * Alcohol or drug abuse within the past 6 months * Hemochromatosis or other iron storage disorders * Pregnant * Any other laboratory abnormality, medical condition, or psychiatric disorders which in the opinion of the Investigator would put the subject's disease management at risk or may result in the subject being unable to comply with the study requirements