Combined chelation therapy with deferasirox and deferoxamine in thalassemia

Abstract

Iron overload is the primary cause of mortality and morbidity in thalassemia major despite advances in chelation therapy. We performed a pilot clinical trial to evaluate the safety and efficacy of combined therapy with deferasirox (DFX, 20-30 mg/kg daily) and deferoxamine (DFO, 35-50mg/kg on 3-7 days/week) in 22 patients with persistent iron overload or organ damage. In the 18 subjects completing 12 months of therapy, median liver iron concentration decreased by 31% from 17.4 mg/g (range 3.9-38.2mg/g) to 12.0mg/g (range 0.96-26.7 mg/g, p<0.001). Median ferritin decreased by 24% from 2465 ng/mL (range 1110-10,700 ng/mL) to 1875 ng/mL (range 421-5800 ng/mL, p=0.002). All 6 subjects with elevated myocardial iron showed improvement in MRI T2* (p=0.031). The mean±S.E. plasma non-transferrin-bound iron (NTBI) declined from 3.10±0.25μM to 2.15±0.29μM (p=0.028). The administration of DFX during infusion of DFO further lowered NTBI (-0.28±0.08 μM, p=0.004) and labile plasma iron (LPI, -0.03±0.01 μM, p=0.006). The simultaneous administration of DFO and DFX rapidly reduced systemic and myocardial iron, and provided an excellent control of the toxic labile plasma iron species without an increase in toxicity.