Ferumoxytol is an intravenous
iron preparation for treatment of the
anemia of
chronic kidney disease (CKD). It is a
carbohydrate-coated, superparamagnetic iron oxide nanoparticle. Because little free
iron is present in the preparation, doses of 510 mg have been administered safely in as little as 17 seconds. Two prospective, randomized studies compared two doses of
ferumoxytol 510 mg given in 5 +/- 3 days with 3 weeks of oral
iron 200 mg/day (as
ferrous fumarate) in anemic patients with CKD. One study enrolled 304 patients with stages 1-5 CKD (predialysis), and the other study enrolled 230 patients with stage 5D CKD (undergoing
hemodialysis). In both studies, a greater increase in
hemoglobin level from baseline to end of study (day 35) was noted in patients who received
ferumoxytol compared with those who received oral
iron (mean +/- SD 0.82 +/- 1.24 vs 0.16 +/- 1.02 g/dl in patients with stages 1-5 CKD and 1.02 +/- 1.13 vs 0.46 +/- 1.06 g/dl in patients with stage 5D CKD, p<0.001). A greater proportion of both predialysis and
hemodialysis patients who received
ferumoxytol had
hemoglobin level increases from baseline of 1 g/dl or more compared with those who received oral
iron (p<0.001). In a prospective, double-blind, crossover study of more than 700 patients with CKD stages 1-5D that compared the safety of
ferumoxytol with
normal saline injection, the rates of treatment-related adverse events were 5.2% and 4.5%, respectively. Serious treatment-related adverse events were seen in one patient in each treatment group. The most common adverse events with
ferumoxytol occurred at the injection site (bruising,
pain, swelling,
erythema).
Dizziness,
nausea,
pruritus,
headache, and
fatigue occurred in less than 2% of patients receiving
ferumoxytol, with a similar frequency noted after administration of
normal saline. In short-term studies, intravenous
ferumoxytol was safely and rapidly administered, and was more effective than oral
iron therapy in increasing
hemoglobin levels in anemic patients with CKD. Long-term clinical trials with clinical outcomes and studies comparing
ferumoxytol with other parenteral
iron agents will help define the role of
ferumoxytol in treating the
anemia of CKD.