Ferumoxytol for the treatment of iron deficiency anemia

Ferumoxytol is a superparamagnetic molecule originally developed as a contrast agent for magnetic resonance imaging. Elemental iron is contained within the carbohydrate core and is released slowly after infusion allowing a large dose of iron to be administered in a short period of time. Ferumoxytol, originally approved for iron deficiency in chronic kidney disease, received a broad label for any cause of iron deficiency after oral iron intolerance or in those circumstances when oral iron is ineffective or harmful. Areas covered: The chemistry, pharmacology and pharmacokinetics of ferumoxytol were reviewed. Retrospective, observational, and prospective phase II and III trials were reviewed. When appropriate, comparative safety and efficacy parameters were reported. Differentiation between minor infusion reactions and more severe hypersensitivity reactions that may lead to anaphylaxis is described. Expert commentary: Ferumoxytol is a safe and effective iron formulation providing a means of iron repletion in persons with iron deficiency with or without anemia. Relative to iron sucrose, ferric gluconate, and iron dextran and similar to ferric carboxymaltose and iron isomaltoside, ferumoxytol yields relatively low quantities of labile free iron. Hypersensitivity and anaphylaxis is extremely rare. Hypophosphatemia with ferumoxytol's administration is extremely rare. Optimal strategies for application of ferumoxytol-enhanced imaging and full replacement dosing in a single setting remain to be determined.