Ferric Carboxymaltose vs Iron Isomaltoside in treating Iron-Deficiency Anemia

The new IV iron, iron isomaltose, which has recently become commercially available in several European countries, is composed of iron and chemically modified isomalto-oligosaccharides which have a mean molecular weight of 1000 Da and consist predominantly of 3–5 glucose units. In contrast to dextrans, the carbohydrate isomaltoside 1000 is a linear and unbranched structure with theoretically a low immunological potential. Hence, a test dose is not necessary according to the product labelling. Iron isomaltoside 1000 contains strongly bound iron within the iron–isomaltoside formulation, which enables a controlled, slow release of bioavailable iron to the iron-binding proteins, with potentially a reduced risk of free iron toxicity.

Ferric carboxymaltose (Ferinject(R)), a novel iron complex that consists of a ferric hydroxide core stabilized by a carbohydrate shell, allows for controlled delivery of iron to target tissues. Administered intravenously, it is effective in the treatment of iron-deficiency anaemia, delivering a replenishment dose of up to 1000 mg of iron during a minimum administration time of </=15 minutes. Results of several randomized trials have shown that intravenously administered ferric carboxymaltose rapidly improves haemoglobin levels and replenishes depleted iron stores in various populations of patients with iron-deficiency anaemia, including those with inflammatory bowel disease, heavy uterine bleeding, postpartum iron-deficiency anaemia or chronic kidney disease. It was well tolerated in clinical trials. Ferric carboxymaltose is, therefore, an effective option in the treatment of iron-deficiency anaemia in patients for whom oral iron preparations are ineffective or cannot be administered. Ferric carboxymaltose is a macromolecular ferric hydroxide carbohydrate complex, which allows for controlled delivery of iron within the cells of the reticuloendothelial system and subsequent delivery to the iron-binding proteins ferritin and transferrin, with minimal risk of release of large amounts of ionic iron in the serum. Intravenous administration of ferric carboxymaltose results in transient elevations in serum iron, serum ferritin and transferrin saturation, and, ultimately, in the correction of haemoglobin levels and replenishment of depleted iron stores.

Iron-deficiency anemia is today’s global health issue. Iron isomaltoside 1000 now known as ferric derisomaltose and ferric carboxymaltose are intravenous iron formulations developed to treat those who are suffering from iron-deficiency anemia, especially in patients who do not tolerate or fail to respond to oral iron. Risks of hypophosphatemia following iron replacement with iron isomaltoside 1000 vs ferric carboxymaltose:

There are randomized trials twice on 245 patients in total.?In trial A: number = 123 & in trial B: number = 122 suffering from iron-deficiency anemia (either intolerant to or unresponsive to oral iron). It was found that the incidence of hypophosphatemia with iron-isomaltoside, when compared with ferric carboxymaltose was 7.9% vs 75% in the trial A and 8.1% vs 73.7% in trial B for over 35 days.

The differences were statistically important.

The Conclusion: We can thus say that iron isomaltoside when compared with ferric carboxymaltose resulted in lower incidence of hypophosphatemia. However, further research is required to determine the findings.