The Shuttle Effect : Combination Therapy With Deferiprone and Deferasirox in Transfusion-dependent Thalassemia Patients.

Background: Three iron chelators now available on the market differ in toxicity and organ specificity; evidence on standardized chelation protocol remains inconclusive, but patients with transfusion-dependent beta-thalassemia treated with DFO infusion show significant differences in the limitations of daily activities, physical activity, and quality of life when treated with oral chelator. With licensing of DFP in America, it is reasonable to combine DFP with DFX. Patients find two oral chelators more acceptable than one oral and one injectable. This pilot study rates use of DFP for improving iron excretion profile of deferasirox.

Methods: The investigators enrolled 13 beta-thalassemia patients in China Medical University Children's Hospital in May 2009-October 2011. Five refused to take part in pharmacokinetics; they only participated in iron excretion study. Seven with irregular bowel function were unable to collect feces in the screening period as baseline data. Subjects were randomly assigned and rotated to undergo all treatments (with informed consent): (A) single oral dose of DFX 30 mg/kg once daily, (B) single oral dose of DFP 40 mg/kg twice a day, (C) oral doses of DFX and DFP administered sequentially (DFX 30 mg/kg/d, deferiprone 40 mg/kg/d and deferiprone 40 mg/kg/d at 7-hour intervals). Three-day drug dosage was followed by four-day washout. Collections of urine and stool proceeded 24 hours per day, each analyzed separately. Through a venous catheter, serial blood samples (1 mL/each sampling) were collected in glass tubes containing heparin as anticoagulant at Time 0 (pre-dosing) and at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 6, 7, 8, 10, 12 and 24 hours after dose; plasma concentrations of DFP and DFX were measured.