Combined iron chelation therapy

Renzo Galanello1, Annalisa Agus, Simona Campus

  • 1Pediatric Clinic 2, University of Cagliari, Italy. renzo.galanello@mcweb.unica.it

Patients with thalassemia major accumulate body iron over time as a consequence of continuous red blood cell transfusions which cause hepatic, endocrine, and cardiac complications. Despite the availability of three iron chelators, some patients fail to respond adequately to monotherapy with any of them. Combination therapy, consisting in the use of two chelators on the same day, has been introduced to increase the efficacy and to induce negative iron balance in patients with severe iron overload. Extensive long-term experience has shown that combined chelation with deferiprone and deferoxamine (DFO) rapidly reduces liver iron, serum ferritin, and myocardial siderosis, improves cardiac function, reverses and prevents endocrine complications, reduces cardiac mortality, and improves survival. Side effects, though significant, are manageable if properly monitored. Preliminary promising results have been obtained using combined chelation with deferasirox and DFO. As more drug combination regimes are evaluated, it should be possible to better tailor iron chelation to the needs of the patients, minimizing toxicity and maximizing efficacy throughout life.

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