Oral iron supplements often fail to maintain adequate iron stores in hemodialysis patients treated with epoetin alfa. Although the hematocrit may show transient improvement using these agents, iron losses during hemodialysis exceed the GI absorption of exogenous iron in most patients, leading to a decrease and eventual deficit in iron stores.

IV iron therapy has been shown to improve responsiveness to epoetin alfa in anemic patients, particularly those with absolute iron deficiency. In addition, studies have shown that frequent administration of low doses of IV iron improves hemoglobin and hematocrit levels and can reduce epoetin alfa requirements in hemodialysis patients.18-21

Epoetin alfa has also been useful in treating the anemia of patients with chronic disease. Typically, serum iron levels are reduced and stored iron levels are normal or even elevated in these patients. Nevertheless, studies have found coadministration of IV iron to be beneficial in a proportion of these patients, suggesting the presence of a functional iron deficiency. This postulate has been raised by several groups to explain the 50% response rate to epoetin alfa among patients with solid tumors, and clinical trials are currently ongoing to obtain a definitive answer to this question.22,23 In addition, iron supplementation alone has been found to be a key component in the alleviation of the anemia associated with Crohn’s disease. 24