Randomized phase II trial of deferasirox (Exjade, ICL670), a once-daily, orally-administered iron chelator, in comparison to deferoxamine in thalassemia patients with transfusional iron overload. A phase 3 study of deferasirox (ICL670), a once-daily oral iron chelator, in patients with beta-thalassemia. A randomised comparison of deferasirox versus deferoxamine for the treatment of transfusional iron overload in sickle cell disease. Deferiprone versus deferoxamine in patients with thalassemia major: a randomized clinical trial. Randomized controlled trial of deferiprone or deferoxamine in beta-thalassemia major patients with asymptomatic myocardial siderosis. A randomized controlled study evaluating the safety and efficacy of deferiprone treatment in thalassemia major patients from Hong Kong. Comparative efficacy of desferrioxamine, deferiprone and in combination on iron chelation in thalassemic children. Comparison between desferrioxamine and combined therapy with desferrioxamine and deferiprone in iron overloaded thalassaemia patients. Evaluation of a new method of administration of the iron chelating agent deferoxamine.
Iron accumulation is an inevitable consequence of chronic blood transfusions and results in serious complications in the absence of chelation treatment to remove excess iron. Deferoxamine (Desferal, DFO) reduces morbidity and mortality although the administration schedule of slow, parenteral infusions several days each week limits compliance and negatively affects long-term outcome. Deferasirox (Exjade, ICL670) is an oral chelator with high iron-binding potency and selectivity. In a phase II study, the tolerability and efficacy of deferasirox were compared with those of DFO in 71 adults with transfusional hemosiderosis.
                Patients were randomized to receive once-daily deferasirox (10 or 20 mg/kg; n=24 in both groups) or DFO (40 mg/kg, 5 days/week; n=23) for 48 weeks. Results. Both treatments were well tolerated and no patient discontinued deferasirox due to drug-related adverse events. The reported frequency of transient, mild to moderate gastrointestinal disturbances was higher in the deferasirox group than in the DFO group, but these disturbances settled spontaneously without dose interruption in all patients. Decreases in liver iron concentration (LIC) were comparable in the deferasirox 20 mg/kg/day and DFO groups; baseline values of 8.5 and 7.9 mg Fe/g dw fell to 6.6 and 5.9 mg Fe/g dw, respectively, by week 48. Deferasirox showed a plasma elimination half-life of 8-16 hours, supporting its once-daily administration.
                Deferasirox at daily doses of 10 or 20 mg/kg was well tolerated and, at 20 mg/kg, showed similar efficacy to DFO 40 mg/kg in terms of decreases in LIC. Deferasirox (ICL670) is a once-daily oral iron chelator developed for the treatment of chronic iron overload from blood transfusions. A comparative phase 3 trial was conducted to demonstrate the efficacy of deferasirox in regularly transfused patients with beta-thalassemia aged 2 years or older. Patients were randomized and received treatment with deferasirox (n = 296) or deferoxamine (n = 290), with dosing of each according to baseline liver iron concentration (LIC). The primary endpoint was maintenance or reduction of LIC; secondary endpoints included safety and tolerability, change in serum ferritin level, and net body iron balance. In both arms, patients with LIC values of 7 mg Fe/g dry weight (dw) or higher had significant and similar dose-dependent reductions in LIC and serum ferritin, and effects on net body iron balance. However, the primary endpoint was not met in the overall population, possibly due to the fact that proportionally lower doses of deferasirox relative to deferoxamine were administered to patients with LIC values less than 7 mg Fe/g dw. The most common adverse events included rash, gastrointestinal disturbances, and mild nonprogressive increases in serum creatinine. No agranulocytosis, arthropathy, or growth failure was associated with deferasirox administration. Deferasirox is a promising once-daily oral therapy for the treatment of transfusional iron overload. Deferasirox is a once-daily, oral iron chelator developed for treating transfusional iron overload. Preclinical studies indicated that the kidney was a potential target organ of toxicity. As patients with sickle cell disease often have abnormal baseline renal function, the primary objective of this randomised, open-label, phase II trial was to evaluate the safety and tolerability of deferasirox in comparison with deferoxamine in this population. Assessment of efficacy, as measured by change in liver iron concentration (LIC) using biosusceptometry, was a secondary objective. A total of 195 adult and paediatric patients received deferasirox (n = 132) or deferoxamine (n = 63). Adverse events most commonly associated with deferasirox were mild, including transient nausea, vomiting, diarrhoea, abdominal pain and skin rash. Abnormal laboratory studies with deferasirox were occasionally associated with mild non-progressive increases in serum creatinine and reversible elevations in liver function tests. Discontinuation rates from deferasirox (11.4%) and deferoxamine (11.1%) were similar. Over 1 year, similar dose-dependent LIC reductions were observed with deferasirox and deferoxamine. Once-daily oral deferasirox has acceptable tolerability and appears to have similar efficacy to deferoxamine in reducing iron burden in transfused patients with sickle cell disease. Deferiprone has been suggested as an effective oral chelation therapy for thalassemia major. To assess its clinical efficacy, we compared deferiprone with deferoxamine in a large multicenter randomized clinical trial. One-hundred forty-four consecutive patients with thalassemia major and serum ferritin between 1500 and 3000 ng/ml were randomly assigned to deferiprone (75 mg/kg/day) (n = 71) or deferoxamine (50 mg/kg/day) (n = 73) for 1 year. The main measure of efficacy was the reduction of serum ferritin. Liver and heart iron contents were assessed by magnetic resonance. Liver iron content and fibrosis stage variations were assessed on liver biopsy by the Ishak score in all patients willing to undergo liver biopsy before and after treatment. The mean serum ferritin reduction was 222 +/- 783 ng/ml in the deferiprone and 232 +/- 619 ng/ml in the deferoxamine group (P = 0.81). No difference in the reduction of liver and heart iron content was found by magnetic resonance between the two groups. Thirty-six patients accepted to undergo repeat liver biopsy: 21 in the deferiprone and 15 in the deferoxamine group. Their mean reduction of liver iron content was 1022 +/- 3511 microg/g of dry liver and 350 +/- 524, respectively (P = 0.4). No difference in variation of the Ishak fibrosis stage was observed between the two groups. Treatment was discontinued because of reversible side effects in 5 patients in the deferiprone group (3 hypertransamin/asemia and 2 leukocytopenia) and in none in the deferoxamine group. These findings suggest that deferiprone may be as effective as deferoxamine in the treatment of thalassemia major with few mild and reversible side effects. Most deaths in beta-thalassemia major result from cardiac complications due to iron overload. Differential effects on myocardial siderosis may exist between different chelators. A randomized controlled trial was performed in 61 patients previously maintained on subcutaneous deferoxamine. The primary end point was the change in myocardial siderosis (myocardial T2(*)) over 1 year in patients maintained on subcutaneous deferoxamine or those switched to oral deferiprone monotherapy. The dose of deferiprone was 92 mg/kg/d and deferoxamine was 43 mg/kg for 5.7 d/wk. Compliance was 94% +/- 5.3% and 93% +/- 9.7% (P = .81), respectively. The improvement in myocardial T2(*) was significantly greater for deferiprone than deferoxamine (27% vs 13%; P = .023). Left ventricular ejection fraction increased significantly more in the deferiprone-treated group (3.1% vs 0.3% absolute units; P = .003). The changes in liver iron level (-0.93 mg/g dry weight vs -1.54 mg/g dry weight; P = .40) and serum ferritin level (-181 microg/L vs -466 microg/L; P = .16), respectively, were not significantly different between groups. The most frequent adverse events were transient gastrointestinal symptoms for deferiprone-treated patients and local reactions at the infusion site for deferoxamine. There were no episodes of agranulocytosis. Deferiprone monotherapy was significantly more effective than deferoxamine over 1 year in improving asymptomatic myocardial siderosis in beta-thalassemia major. A controlled, open-label and randomized study was conducted to evaluate the safety and efficacy of the oral iron chelator deferiprone (L1) in thalassemia major patients from Hong Kong. Forty-nine patients were recruited in total (median age: 20 years; range: 8 to 40 years). The division of the patients was determined based on liver iron content and put into either the poorly-chelated (Group I) or well-chelated (Group II) groups. In Group I, 20 patients received combined therapy of L1 daily plus desferrioxamine (DFO), in a reduced frequency of twice weekly, while the control group consisted of 16 patients who were treated with DFO alone. In Group II, six patients received L1 only, while the control group consisted of seven patients treated with DFO alone. Only patients who participated for longer than 6 months were analyzed for efficacy (n = 44). The median study period was 18 months. Transient and mild gastrointestinal upset (31%), joint pain (15%) and liver enzyme elevation (23%) were the most common side effects noted for L1. No case of neutropenia was observed in this study. Serum ferritin (SF) levels showed significant decline in the poorly-chelated patients using combined therapy (L1 and reduced frequency DFO) as compared to those on DFO alone. However, their pre- and post-study liver iron content was not significantly different. Evaluation of the well-chelated group demonstrated no significant change in SF or liver iron content in both the study and control arms. We conclude that the short-term use of L1, with or without DFO, was safe and efficacious in our Chinese patient cohort. The long-term efficacy of reducing iron overload by treatment regimens including L1 requires further study. Ascertainment of an appropriate strategy of iron chelation for multi-transfused thalassemic children in developing countries.
                Prospective study from May 2000 to April 2001.
                Urban tertiary care center.
                Thirty thalassemic children having received more than 20 blood transfusions and a serum ferritin greater than 1500 ng/ml were enrolled and randomized into three groups. Group I received desferrioxamine (DFX) at a dose of 40 mg/kg subcutaneously, 5 days/week. Children in group II received oral deferiprone (L1) at a dose of 75 mg/kg/day daily and group III received a combination of daily L1 at a dose of 75 mg/kg/day and DFX at a dose of 40 mg/kg/day two times per week. The assessment of chelation was done by 24-hr urinary iron excretion (UIE) and measurement of serum ferritin levels at start and after 6 months of follow up. Statistical difference of serum ferritin levels between the three groups was assessed by applying analysis of variance. Analysis of covariance was applied to find out the urinary iron excretion keeping serum ferritin values same in each groups.
                Ferritin levels after 6 months of intervention were maximally decreased in group I. There was a significant difference between groups I and II however, no difference was noted between groups I and group III. There was no statistically significant difference in mean urinary iron excretion by keeping the initial serum ferritin levels equal though it was found to be more in group III as compared to other groups.
                DFX is the most effective chelating drug in iron overloaded multi-transfused thalassemic patients. In view of cost and unacceptability of daily DFX injections, combination therapy is an effective method of chelation thus increasing the compliance and cost effectiveness. Deferiprone (L1) alone is not an effective mode of chelation when used for a short period. Desferrioxamine (DFX) alone (40-50 mg/kg/d s.c. over 8-12 h, five times weekly) was compared with combined DFX twice weekly and deferiprone (75 mg/kg/d) over 12 months in previously poorly chelated thalassaemia patients. Serum ferritin fell from 5506 +/- 635 microg/l (mean +/- SEM) to 3998 +/- 604 microg/l (P < 0.001; n = 14) in the DFX group and from 4153 +/- 517 microg/l to 2805 +/- 327 microg/l in the combined group (P < 0.01; n = 11). Deferiprone plus DFX produced a greater mean urine iron excretion (1.01 mg/kg/24 h) than iron intake from blood transfusion in each patient. Main side-effects were skin reactions (DFX alone), nausea and arthralgia (combined therapy). As chelation therapy, the combined protocol was as effective as DFX five times weekly. We compared the effectiveness of deferoxamine administered by twice-daily subcutaneous injections with conventional administration by prolonged subcutaneous infusion in 20 patients with thalassemia. Urinary iron excretion was comparable with the two methods but decreased significantly when the total daily dose was administered as a single injection. Local reactions were similar with infusion and injection. Subcutaneous injections of deferoxamine may be considered as an alternative to conventional infusions.
Deferasirox offers an important alternative line of treatment for people with thalassaemia and secondary iron overload. Based on the available data, deferasirox does not seem to be superior to deferoxamine at the usually recommended ratio of 1 mg of deferasirox to 2 mg of deferoxamine. However, similar efficacy seems to be achievable depending on the dose and ratio of deferasirox compared to deferoxamine. Whether this will result in similar efficacy in the long run and will translate to similar benefits as has been shown for deferoxamine, needs to be confirmed. Data on safety, particularly on rare toxicities and long-term safety, are still limited.
Therefore, we think that deferasirox should be offered as an alternative to all patients with thalassaemia who either show intolerance to deferoxamine or poor compliance with deferoxamine. In our opinion, data are still too limited to support the general recommendation of deferasirox as first-line treatment instead of deferoxamine. If a strong preference for deferasirox is expressed, it could be offered as first-line option to individual patients after a detailed discussion of the potential benefits and risks.