Iron deficiency is an important clinical concern in chronic kidney disease (CKD), giving rise to iron deficiency anemia and various impaired cellular functions. Iron therapy, with or without concomitant administration of erythropoiesis-stimulating agents (ESAs), has been used in the management of anemia in the CKD for many years. More recently, the use of iron therapy as a means to delay the need for alternative anemia management in the predialysis population or to lower the required dosage of ESAs in the hemodialysis (HD) population has come to the fore.

Having decided that the initiation of iron therapy is necessary, the clinician must next decide whether oral or intravenous (IV) administration will be best for the individual patient. The KDIGO guideline does not recommend the use of oral iron in CKD-5D patients but suggests that either oral or IV iron may be considered in CKD-ND (nondialysis) patients. For CKD-ND patients it is suggested that the selection of oral versus IV administration should consider the severity of anemia, availability of venous access, response to prior therapy, patient adherence and cost.

IV administration of iron has been demonstrated to be more effective than oral administration with respect to the elevation of hemoglobin (Hb), ferritin and transferrin saturation (TSAT) levels in patients with CKD-5D and in those with CKD-ND. Patients receiving IV iron have also been shown to achieve target Hb levels more quickly. In patients on HD, IV iron has become standard-of-care because it allows correction of iron deficiency anemia in most instances, especially when using high iron doses. Recently, the PIVOTAL study suggested the proactive use of high-dose IV iron can reduce the amount of ESA needed to treat anemia in dialysis patients with no short-term increase in the risk for vascular complications or infections. Furthermore, ESA dose requirements are lower in patients treated with IV iron compared with those receiving oral iron.

While clinical practice guidelines provide general recommendations for the use of iron in the management of anemia associated with CKD, their application in clinical practice must be tailored to meet the needs of the individual patient. Findings from a number of studies assessing the safety and efficacy of IV iron in CKD-ND patient population have been published in the intervening years. As a result, IV iron may become the preferred initial treatment option for physicians wanting to increase Hb concentrations or delay alternative anemia management in patients with CKD-ND. Ferric carboxymaltose is a robust and stable molecule with similar characteristics to ferritin, which minimizes the release of free iron during its administration, this allows greater iron delivery to tissues and a faster repletion of iron stores by a single infusion, with favorable cost-effectiveness.