Emerging Therapies for Iron Deficiency in Anemia of  CKD

Individuals with chronic kidney disease (CKD) commonly experience iron deficiency associated with anemia. In an article online in the American Journal of Kidney Diseases [doi.org/10.1053/j.ajkd.2021.09.017], Jonathan W. Bazeley, MD, and Jay B. Walsh, MD, provide an explanation of diagnostic criteria for iron deficiency in CKD, as well as a review of the mechanisms of functional and absolute iron deficiency and general treatment principles as outlined in the Kidney Disease: Improving Global Outcomes guidelines.

Over time, there has been progress in the repletion of absolute iron deficits due to better tolerated and more effective agents, such as ferric citrate, ferric maltol, and sucrosomial iron. The review examines the structural characteristics and data from clinical trials that enabled regulatory approval of those agents.

Newer intravenous iron therapies including ferric carboxymaltose and ferric derisomaltose allow for fewer infusions and a decreased risk of serious hypersensitivity reactions.

The review also includes concerns regarding adverse events, including cardiovascular events and infections. The authors emphasize the potential risk of 6H syndrome associated with the new intravenous agents, such as hypophosphatemia, osteomalacia, and pathologic fractures, and describe the proposed pathophysiology of 6H syndrome and hypophosphatemia.

Ferric pyrophosphate citrate enables administration of iron for repletion through dialysate. The review summarizes the relative merits, costs, and risk of various iron agents.