Efficacy and safety of IV ferumoxytol for adults with iron deficiency anemia previously unresponsive to or unable to tolerate oral iron.

Although oral iron is the initial treatment approach for iron deficiency anemia (IDA), some patients fail to respond to or cannot tolerate oral iron. This double-blind safety and efficacy study of the intravenous (IV) iron, ferumoxytol, randomized patients with a history of unsatisfactory oral iron therapy, or in whom oral iron could not be used, to ferumoxytol (n = 609) or placebo (n = 203). The proportion of patients achieving the primary endpoint (hemoglobin increase ≥2.0 g/dL at Week 5) was 81.1% with ferumoxytol versus 5.5% with placebo (P < 0.0001). The mean increase in hemoglobin from Baseline to Week 5, a secondary endpoint (also the alternative preplanned primary efficacy endpoint for other health authorities), was 2.7 versus 0.1 g/dL (P < 0.0001). Achievement of a hemoglobin ≥12 g/dL, time to a hemoglobin increase ≥2.0 g/dL, and improvement in the Functional Assessment of Chronic Illness Therapy Fatigue score also significantly favored ferumoxytol over placebo at Week 5 (P < 0.0001). Ferumoxytol treatment-emergent adverse events were mainly mild to moderate. Ferumoxytol was effective and well tolerated in patients with IDA of any underlying cause in whom oral iron was ineffective or could not be used. This trial was registered at www.clinicaltrials.gov as #NCT01114139.