OBJECTIVES

Iron deficiency anemia (IDA) arises when iron losses or requirements exceed absorption, and is often multifactorial in its etiology. Intravenous (IV) is the preferred mode of iron administration in certain groups of patients with IDA, as the efficacy of oral iron is limited by gastrointestinal (GI) absorption and can result in adverse GI symptoms and treatment discontinuation. The aim of the present study was to evaluate the relative efficacy of two high-dose IV iron formulations: iron isomaltoside (IIM) and ferric carboxymaltose (FCM) in patients with IDA.

METHODS

Literature databases were systematically searched to identify randomized controlled trials (RCTs) comparing IIM with FCM in patients with IDA, and RCTs of IIM and FCM with common comparators in order to conduct an indirect treatment comparison (ITC). An ITC of IIM and FCM was ultimately conducted via iron sucrose, employing the Bucher method and evaluating change from baseline hemoglobin and proportion of patients achieving a clinically-relevant response.

RESULTS

The systematic literature review identified no direct RCT comparisons of IIM and FCM that had reported results, 5 RCTs of IIM (4 versus oral iron and 1 versus iron sucrose), and 14 RCTs of FCM (11 versus oral iron and 3 versus iron sucrose). Change from baseline hemoglobin significantly favored IIM with a mean difference of +0.249 g/dL (95% confidence interval 0.072-0.426 g/dL) with IIM relative to FCM.

CONCLUSIONS

Based on an ITC via iron sucrose, IIM would result in a larger increase from baseline hemoglobin than FCM. The proportion of patients achieving clinically-relevant response was not significantly different, but directionally favored IIM over FCM. Due to the heterogeneity between the studies included in the ITC, direct comparisons of IIM and FCM would be needed to confirm these findings.