Comparing the efficacy of intravenous iron and oral iron in nondialysis patients with chronic kidney disease.

This Practice Point commentary discusses the findings and limitations of a phase III trial by Spinowitz et al. that compared oral and intravenous iron therapies in nondialysis patients with chronic kidney disease. In total, 304 patients were randomly assigned in a 3:1 ratio to receive either two 510 mg doses of intravenous ferumoxytol within 5+/-3 days or 200mg of elemental oral iron daily for 21 days. At day 35, hemoglobin levels had increased significantly more in patients who had received intravenous ferumoxytol than in those who had received oral iron therapy. Ferumoxytol was well tolerated. The superiority of ferumoxytol over other intravenous iron preparations, however, needs to be investigated, and optimal serum ferritin levels for the nondialysis CKD population need to be defined.