Ferumoxytol Use as an Intravenous Contrast Agent for Magnetic Resonance Angiography

OBJECTIVE: To evaluate the efficacy and safety of ferumoxytol for use in magnetic resonance angiography (MRA) of the vasculature. DATA SOURCES: Literature was accessed through MEDLINE (1946-September 2011) and EMBASE (1947-September 2011) using the terms ferumoxytol, magnetic resonance imaging and angiography, blood pool agent, and superparamagnetic iron oxide. Reference citations from identified publications were reviewed for relevant information. STUDY SELECTION AND DATA EXTRACTION: All English-language articles and human studies (N = 9) were identified that evaluated ferumoxytol use in magnetic resonance imaging (MRI). Articles that evaluated the use of the drug in first-pass and equilibrium phase imaging of the vasculature were included (n = 4). DATA SYNTHESIS: Contrast agents for MRI improve disease characterization and diagnosis. Ferumoxytol, a medication approved for treatment of iron deficiency anemia in adults with chronic kidney disease, has superparamagnetic properties. As a blood pool agent, ferumoxytol remains primarily in the intravascular space. Therefore, its use in MRI may increase image sensitivity and specificity and have a decreased adverse effect profile compared to other contrast agents. Specifically, ferumoxytol may be an option for MRA, a specific type of MRI that images blood vessels. In the 4 studies evaluated here, ferumoxytol was administered primarily to healthy adults as an accumulative dose of 4 mg Fe/kg injected at 1 mL/sec. Not all studies reported adverse events and addressed safety monitoring. The evaluated studies are limited by small size, open-label design, and noncomparative methodology. CONCLUSIONS: Data from small pilot studies suggest that ferumoxytol may improve image quality in MRA; however, further investigation is necessary to establish its efficacy and safety. Large randomized, active-comparator trials are needed to establish optimal dosing, imaging procedures, and safety monitoring.