Intravenous iron isomaltoside improves hemoglobin concentration and iron stores in female iron-deficient blood donors: a randomized double-blind placebo-controlled clinical trial

BACKGROUND: This trial evaluated the efficacy and safety of intravenous (IV) iron isomaltoside (Monofer) in comparison with placebo in first-time female blood donors. STUDY DESIGN AND METHODS: The trial was a prospective, double blind, placebo-controlled, randomized, comparative, single-center trial of 85 first-time female blood donors. The subjects were randomly assigned 1:1 to either 1000 mg IV iron isomaltoside infusion or placebo. The primary endpoint of the trial was change in hemoglobin (Hb) from baseline to right before the third blood donation. RESULTS: The increase in Hb was significantly higher for iron isomaltoside compared with placebo right before both the second blood donation (p = 0.0327) and the third blood donation (primary endpoint, p < 0.0001). Improvements in other iron-related variables (plasma iron, plasma ferritin, transferrin saturation, and reticulocyte count) in favor of iron isomaltoside were also observed. The trial was not powered on patient-reported outcomes. However, improvements in iron stores and Hb levels after iron isomaltoside administration were supported by the fact that several of the fatigue symptoms scores showed numerical differences in favor of iron isomaltoside. There were no differences in side effects between the groups. CONCLUSION: In iron-deficient female blood donors a single IV iron isomaltoside administration resulted in an improvement in Hb concentration and iron stores and demonstrated a favorable safety profile comparable to placebo.