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Aydinok Y. Combination chelation therapy. Ann N Y Acad Sci 2023; 1529:33-41. [PMID: 37594980 DOI: 10.1111/nyas.15052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
Abstract
Combination chelation therapies are considered in transfusion-dependent thalassemia patients for whom monotherapy regimens have failed to achieve iron balance or intensification of iron chelation therapy is required for the rapid reduction of excess iron to avoid permanent organ damage. Combination chelation may provide a more flexible approach for individualizing chelation therapy, thereby improving tolerability, adherence, and quality of life. In principle, iron chelators can be combined with an infinite number of dosing regimens; these involve simultaneous or sequential exposure to the chelators on the same day or alternating the drugs on different days. Clinical studies have established the safety and efficacy of chelation combinations. However, real-life data with combination therapies indicate the significance of compliance for a meaningful reduction in iron overload compared to monotherapies.
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Affiliation(s)
- Yesim Aydinok
- Department of Pediatric Hematology, School of Medicine, Ege University, Izmir, Turkey
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2
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Shah R, Shah A, Badawy SM. An evaluation of deferiprone as twice-a-day tablets or in combination therapy for the treatment of transfusional iron overload in thalassemia syndromes. Expert Rev Hematol 2023; 16:81-94. [PMID: 36755516 PMCID: PMC9992344 DOI: 10.1080/17474086.2023.2178409] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 02/06/2023] [Indexed: 02/10/2023]
Abstract
INTRODUCTION Regular blood transfusions in patients with thalassemia syndromes can cause iron overload resulting in complications including cirrhosis, heart problems, or endocrine abnormalities. To prevent iron overload toxicity in these patients, three iron chelators are currently FDA-approved for use: deferoxamine, deferasirox, and deferiprone. In the United States, deferiprone has been approved for three times daily dosing since 2011 and has recently gained approval for twice-daily administration. AREAS COVERED A PubMed literature search was performed with the keywords 'deferiprone' and 'thalassemia.' Relevant original research studying deferiprone's effects on transfusional iron overload in patients with thalassemia syndromes was included. Exclusion criteria included case reports and review papers. Deferiprone is effective at reducing serum ferritin levels in patients with iron overload. Twice-daily administration provides a similar level of iron chelation as three times daily dosing with a comparable side effect profile and increased patient acceptability. EXPERT OPINION New studies are highlighting deferiprone's potential for combination therapy with either deferoxamine or deferasirox to improve iron chelation. Deferiprone's ability to significantly decrease cardiac and liver iron content can be utilized in other transfusion-dependent hematologic conditions, as evidenced by its recent approval for use in the United States for sickle cell disease or other anemias.
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Affiliation(s)
- Richa Shah
- Division of Hematology, Oncology, and Stem Cell Transplant, Lurie Children’s Hospital of Chicago, Chicago, IL, 60611, USA
| | - Aashaka Shah
- University of Illinois College of Medicine, Chicago, IL, 60612, USA
| | - Sherif M. Badawy
- Division of Hematology, Oncology, and Stem Cell Transplant, Lurie Children’s Hospital of Chicago, Chicago, IL, 60611, USA
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
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3
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Binding A, Ward R, Tomlinson G, Kuo KHM. Deferiprone exerts a dose-dependent reduction of liver iron in adults with iron overload. Eur J Haematol 2019; 103:80-87. [PMID: 31066943 DOI: 10.1111/ejh.13244] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/28/2019] [Accepted: 04/30/2019] [Indexed: 01/19/2023]
Abstract
OBJECTIVE While doses of deferiprone up to 75 mg/kg/d have been demonstrated to be effective in cardiac iron removal, their efficacy in the reduction of liver iron has been equivocal. The aim of this study was to evaluate the effect of deferiprone dose on liver iron concentrations in adult iron overload patients. METHODS A single-centered, retrospective, cohort observational study was conducted involving 71 patients exposed to deferiprone doses up to 113 mg/kg/d between January 2009 and June 2015 for a median of 33 months. RESULTS At the end of the study period, liver iron measured by R2 MRI was reduced by a mean 1.7 mg/g dw. A dose effect was observed, with incremental reductions of 2.8 mg/g dw in end of study LIC for every 10 mg/kg/d higher dose of deferiprone (P < 0.001). A dose effect was also observed in end of study ferritin and cardiac iron concentration measured by T2* MRI (P < 0.0001 and P = 0.048, respectively). No associations between adverse effects and deferiprone dose were observed, but there was a trend toward higher rates of agranulocytosis at higher doses and two of three hereditary hemochromatosis patients developed this complication. CONCLUSION The present study failed to demonstrate that the use of deferiprone at >90 mg/kg/d was associated with increased risk of agranulocytosis or neutropenia, but did demonstrate more effective liver iron control in iron overload patients.
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Affiliation(s)
- Andrew Binding
- Division of Hematology, University of Toronto, Toronto, Ontario, Canada.,Divison of Medical Oncology & Hematology, University Health Network, Toronto, Ontario, Canada
| | - Richard Ward
- Division of Hematology, University of Toronto, Toronto, Ontario, Canada.,Divison of Medical Oncology & Hematology, University Health Network, Toronto, Ontario, Canada
| | - George Tomlinson
- Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada.,Department of Public Health Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Kevin H M Kuo
- Division of Hematology, University of Toronto, Toronto, Ontario, Canada.,Divison of Medical Oncology & Hematology, University Health Network, Toronto, Ontario, Canada
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The value of magnetic resonance imaging in evaluation of myocardial and liver iron overload in a thalassaemia endemic population: a report from Northeastern Thailand. Pol J Radiol 2019; 84:e262-e268. [PMID: 31481999 PMCID: PMC6717950 DOI: 10.5114/pjr.2019.86094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 04/25/2019] [Indexed: 12/29/2022] Open
Abstract
Purpose Patients with chronic haemolytic anaemia, such as in thalassaemia, require repeated blood transfusions, which leads to iron overload and cellular damage, especially in the heart and liver. Classically, serum ferritin and liver biopsy have been used to monitor patient response to chelation therapy. Magnetic resonance imaging (MRI) has proven to be effective in detecting and quantifying iron in the heart and liver. The aim of the paper is to evaluate the accuracy of the MRI T2* procedure in the assessment of liver iron concentration and myocardial iron overload. Material and methods In 210 cases of monthly transfused patients, hepatic and myocardial iron overload was measured by multi-breath-hold MRI T2* and compared to serum ferritin (a traditional marker of iron overload). Results No significant correlation was observed between serum ferritin level and cardiac T2* MRI (p = 0.68, r = 0.06). However, a significant correlation was observed between serum ferritin and liver iron concentration evaluated by MRI (p = 0.04, r = 0.68). Conclusion Routine evaluation of liver and heart iron content using MRI T2* is suggested to better evaluate the haemosiderosis status in thalassaemic patients.
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Ceci A, Conte R, Didio A, Bonifazi D, Felisi M, Giannuzzi V, Bonifazi F. An overview of the efficacy and safety of deferiprone in paediatric patients with congenital haemoglobinopathies and chronic iron overload. Expert Opin Orphan Drugs 2019. [DOI: 10.1080/21678707.2019.1613977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Adriana Ceci
- Department of Research, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Bari, Italy
| | - Rosa Conte
- Department of Research, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Bari, Italy
| | - Antonella Didio
- Department of Research, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Bari, Italy
| | - Donato Bonifazi
- Department of Clinical Research, Consorzio per Valutazioni Biologiche e Farmacologiche, Bari, Italy
| | - Mariagrazia Felisi
- Department of Clinical Research, Consorzio per Valutazioni Biologiche e Farmacologiche, Bari, Italy
| | - Viviana Giannuzzi
- Department of Research, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Bari, Italy
| | - Fedele Bonifazi
- Department of Research, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Bari, Italy
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Olivieri NF, Sabouhanian A, Gallie BL. Single-center retrospective study of the effectiveness and toxicity of the oral iron chelating drugs deferiprone and deferasirox. PLoS One 2019; 14:e0211942. [PMID: 30811439 PMCID: PMC6392256 DOI: 10.1371/journal.pone.0211942] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 01/25/2019] [Indexed: 01/19/2023] Open
Abstract
Background Iron overload, resulting from blood transfusions in patients with chronic anemias, has historically been controlled with regular deferoxamine, but its parenteral requirement encouraged studies of orally-active agents, including deferasirox and deferiprone. Deferasirox, licensed by the US Food and Drug Administration in 2005 based upon the results of randomized controlled trials, is now first-line therapy worldwide. In contrast, early investigator-initiated trials of deferiprone were prematurely terminated after investigators raised safety concerns. The FDA declined market approval of deferiprone; years later, it licensed the drug as “last resort” therapy, to be prescribed only if first-line drugs had failed. We undertook to evaluate the long-term effectiveness and toxicities of deferiprone and deferasirox in one transfusion clinic. Methods and findings Under an IRB-approved study, we retrospectively inspected the electronic medical records of consented iron-loaded patients managed between 2009 and 2015 at The University Health Network (UHN), Toronto. We compared changes in liver and heart iron, adverse effects and other outcomes, in patients treated with deferiprone or deferasirox. Results Although deferiprone was unlicensed in Canada, one-third (n = 41) of locally-transfused patients had been switched from first-line, licensed therapies (deferoxamine or deferasirox) to regimens of unlicensed deferiprone. The primary endpoint of monitoring in iron overload, hepatic iron concentration (HIC), increased (worsened) during deferiprone monotherapy (mean 10±2–18±2 mg/g; p < 0.0003), exceeding the threshold for life-threatening complications (15 mg iron/g liver) in 50% patients. During deferasirox monotherapy, mean HIC decreased (improved) (11±1–6±1 mg/g; p < 0.0001). Follow-up HICs were significantly different following deferiprone and deferasirox monotherapies (p < 0.0000002). Addition of low-dose deferoxamine (<40 mg/kg/day) to deferiprone did not result in reductions of HIC to <15 mg/g (baseline 20±4 mg/g; follow-up, 18±4 mg/g; p < 0.2) or in reduction in the proportion of patients with HIC exceeding 15 mg/g (p < 0.2). During deferiprone exposure, new diabetes mellitus, a recognized consequence of inadequate iron control, was diagnosed in 17% patients, most of whom had sustained HICs exceeding 15 mg/g for years; one woman died after 13 months of a regimen of deferiprone and low-dose deferasirox. During deferiprone exposure, serum ALT increased over baseline in 65% patients. Mean serum ALT increased 6.6-fold (p < 0.001) often persisting for years. During deferasirox exposure, mean ALT was unchanged (p < 0.84). No significant differences between treatment groups were observed in the proportions of patients estimated to have elevated cardiac iron. Conclusions Deferiprone showed ineffectiveness and significant toxicity in most patients. Combination with low doses of first-line therapies did not improve the effectiveness of deferiprone. Exposure to deferiprone, over six years while the drug was unlicensed, in the face of ineffectiveness and serious toxicities, demands review of the standards of local medical practice. The limited scope of regulatory approval of deferiprone, worldwide, should restrict its exposure to the few patients genuinely unable to tolerate the two effective, first-line therapies.
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Affiliation(s)
- Nancy F. Olivieri
- Medicine and Public Health Sciences, University of Toronto, Toronto, Ontario, Canada
- Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
- * E-mail:
| | - Amir Sabouhanian
- Medicine and Public Health Sciences, University of Toronto, Toronto, Ontario, Canada
- Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Brenda L. Gallie
- Department of Ophthalmology and Vision Science, Hospital for Sick Children, Toronto, Ontario, Canada
- Departments of Ophthalmology and Vision Science, Medical Biophysics and Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Techna Institute and Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
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Sridharan K, Sivaramakrishnan G. Efficacy and safety of iron chelators in thalassemia and sickle cell disease: a multiple treatment comparison network meta-analysis and trial sequential analysis. Expert Rev Clin Pharmacol 2018; 11:641-650. [PMID: 29727586 DOI: 10.1080/17512433.2018.1473760] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND To compare the efficacy and safety of desferrioxamine (DFO), deferiprone (DFP), deferasirox (DFX) and silymarin in patients with either thalassemia or sickle cell disorder through network meta-analysis. METHODS Electronic databases were searched for appropriate randomized clinical trials comparing iron chelators in patients with iron overload. Random effects model was used to generate direct, indirect and mixed treatment comparison pooled estimates for the following outcomes: serum ferritin, liver iron concentration (LIC), changes in serum ferritin, mortality, urine iron excretion, adverse events, neutropenia, agranulocytosis and number of patients withdrawing the chelating therapy. RESULTS Thirty-two clinical trials were included in the meta-analysis. DFX/DFO was associated with better serum ferritin levels compared to DFO, DFX, DFO/Silymarin and DFP/DFO. DFX/DFO also lower LIC significantly compared to DFO. DFP/DFO was associated with higher LVEF, low risk of adverse events and reduced end of serum ferritin compared to DFO. Combination of silymarin with either DFP or DFX was observed with reduced end of treatment serum ferritin compared to using either of the drugs alone. DFP was observed with better effects in sickle cell disease. The strength of evidence was very low for most of the comparisons. CONCLUSION Relative estimates between the individual iron chelators have been established. However, this evidence should be considered preliminary and may change with the results of future head-to-head clinical trials.
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Affiliation(s)
- Kannan Sridharan
- a Department of Pharmacology and Therapeutics , College of Medicine and Medical Sciences, Arabian Gulf University , Manama , Bahrain
| | - Gowri Sivaramakrishnan
- b School of Oral Health, College of Medicine, Nursing and Health Sciences , Fiji National University , Suva , Fiji islands
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Di Maggio R, Maggio A. The new era of chelation treatments: effectiveness and safety of 10 different regimens for controlling iron overloading in thalassaemia major. Br J Haematol 2017; 178:676-688. [DOI: 10.1111/bjh.14712] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Rosario Di Maggio
- Campus of Haematology Franco and Piera Cutino; AOR Villa Sofia-V. Cervello; Palermo Italy
| | - Aurelio Maggio
- Campus of Haematology Franco and Piera Cutino; AOR Villa Sofia-V. Cervello; Palermo Italy
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10
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Saliba AN, El Rassi F, Taher AT. Clinical monitoring and management of complications related to chelation therapy in patients with β-thalassemia. Expert Rev Hematol 2015; 9:151-68. [DOI: 10.1586/17474086.2016.1126176] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Fahmy HS, Khater NH, El Shahat HM, Madani AA, El Hadidy SS. Reassessing the value of MRI T2∗ in evaluation of hepatic and myocardial iron concentration: An institutional study. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2015. [DOI: 10.1016/j.ejrnm.2015.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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12
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Saliba AN, Harb AR, Taher AT. Iron chelation therapy in transfusion-dependent thalassemia patients: current strategies and future directions. J Blood Med 2015; 6:197-209. [PMID: 26124688 PMCID: PMC4476479 DOI: 10.2147/jbm.s72463] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Transfusional iron overload is a major target in the care of patients with transfusion-dependent thalassemia (TDT) and other refractory anemias. Iron accumulates in the liver, heart, and endocrine organs leading to a wide array of complications. In this review, we summarize the characteristics of the approved iron chelators, deferoxamine, deferiprone, and deferasirox, and the evidence behind the use of each, as monotherapy or as part of combination therapy. We also review the different guidelines on iron chelation in TDT. This review also discusses future prospects and directions in the treatment of transfusional iron overload in TDT whether through innovation in chelation or other therapies, such as novel agents that improve transfusion dependence.
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Affiliation(s)
- Antoine N Saliba
- Department of Internal Medicine, Division of Hematology/Oncology, American University of Beirut, Beirut, Lebanon
| | - Afif R Harb
- Department of Internal Medicine, Division of Hematology/Oncology, American University of Beirut, Beirut, Lebanon
| | - Ali T Taher
- Department of Internal Medicine, Division of Hematology/Oncology, American University of Beirut, Beirut, Lebanon
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Kuo KHM, Mrkobrada M. A systematic review and meta-analysis of deferiprone monotherapy and in combination with deferoxamine for reduction of iron overload in chronically transfused patients with β-thalassemia. Hemoglobin 2014; 38:409-21. [PMID: 25307964 DOI: 10.3109/03630269.2014.965781] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
β-Thalassemia major (β-TM) patients require life-long blood transfusions, resulting in iron overload with multi-organ morbidity and mortality. Evidence from small randomized controlled trials (RCTs) published to date for deferiprone (DFP) monotherapy or in combination with deferoxamine (DFO) is unclear. We summarized evidence on the efficacy of DFP monotherapy compared to DFO, and DFP-DFO combination therapy compared to DFP or DFO monotherapy in chronically transfused β-TM. We searched four electronic databases and examined the grey literature. Two authors independently assessed trial quality and extracted data. We calculated the relative risk for dichotomous outcomes and mean difference (MD) for continuous outcomes. We identified 15 RCTs (1003 participants) that met the inclusion criteria. Deferiprone was more efficacious than DFO in improving cardiac ejection fraction [MD 2.88, 95% CI (95% confidence interval) 1.12 to 4.64, p = 0.001) and endocrine dysfunction (MD 0.09, 95% CI 0.08 to 0.10, p < 0.00001). The DFP-DFO combination therapy was more efficacious than DFP or DFO monotherapy in improving cardiac ejection fraction (MD 5.67, 95% CI 1.32 to 10.02, p = 0.008). There was no significant difference in all other outcomes examined. Meta-analysis on changes in myocardial iron content was not possible due to differences in data presentation. The quality of evidence for all outcomes was low. There is currently insufficient evidence to show that DFP is superior to DFO in the treatment of iron overload. The use of DFP must be weighed against the potential side-effects, patient compliance and preference. Large RCTs with clinically relevant outcomes are required.
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Affiliation(s)
- Kevin H M Kuo
- Red Blood Cell Disorders Program, Division of Medical Oncology and Hematology, University Health Network , Toronto, Ontario , Canada
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14
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Aydinok Y, Kattamis A, Viprakasit V. Current approach to iron chelation in children. Br J Haematol 2014; 165:745-55. [PMID: 24646011 DOI: 10.1111/bjh.12825] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Transfusion-dependent children, mostly with thalassaemia major, but also and occasionally to a more significant degree, with inherited bone marrow failures, can develop severe iron overload in early life. Moreover, chronic conditions associated with ineffective erythropoiesis, such as non-transfusion-dependent thalassaemia (NTDT), may lead to iron overload through increased gut absorption of iron starting in childhood. Currently, the goal of iron chelation has shifted from treating iron overload to preventing iron accumulation and iron-induced end-organ complications, in order to achieve a normal pattern of complication-free survival and of quality of life. New chelation options increase the likelihood of achieving these goals. Timely initiation, close monitoring and continuous adjustment are the cornerstones of optimal chelation therapy in children, who have a higher transfusional requirements compared to adults in order to reach haemoglobin levels adequate for normal growth and development. Despite increased knowledge, there are still uncertainties about the level of body iron at which iron chelation therapy should be started and about the appropriate degree of iron stores' depletion.
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Affiliation(s)
- Yesim Aydinok
- Department of Paediatric Haematology/Oncology, Ege University Children's Hospital, Ege University School of Medicine, Izmir, Turkey
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Viprakasit V, Rodmai S, Srichairatanakool S. Deferiprone for transfusional iron overload and its roles in developing countries. Expert Opin Orphan Drugs 2014. [DOI: 10.1517/21678707.2014.885388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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16
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Xia S, Zhang W, Huang L, Jiang H. Comparative efficacy and safety of deferoxamine, deferiprone and deferasirox on severe thalassemia: a meta-analysis of 16 randomized controlled trials. PLoS One 2013; 8:e82662. [PMID: 24376563 PMCID: PMC3871701 DOI: 10.1371/journal.pone.0082662] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 10/25/2013] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE A meta-analysis was conducted to investigate the efficacy and safety of three main iron chelators, namely, deferoxamine (DFO), deferiprone (DFP) and deferasirox (DFX) for thalassemia major (TM) patients. METHODS Randomized controlled trials comparing mono-therapy DFO, DFP, DFX and combined DFP with DFO therapy in TM patients from January 1990 to December 2012 were searched and selected. Two independent authors assessed data from extracted randomized trials for efficacy and safety in the measurements of serum ferritin (SF), live iron concentration (LIC), myocardial iron content (MIC), left ventricular ejection fraction (LVEF) and adverse events (AEs). RESULTS Sixteen studies were selected. In the comparison of DFP versus DFO treatment groups, a significant difference was revealed on MIC and LVEF (P=0.01 and P=0.007, respectively) but not on SF or LIC level (P=0.65 and P=0.37, respectively). In comparing combined therapy (DFP plus DFO) versus DFO, a significant difference was shown on MIC and LVEF measurements (P<0.00001 and P=0.003, respectively), but not on SF or LIC levels (P=0.93 and P=0.62, respectively). Moreover, the combined DFP with DFO treatment had significantly higher risk than DFO treatment (RR 1.46 with 95%CI 1.04 to 2.04). When comparing DFX with DFO, a significant difference was shown on the SF level (P=0.003), and there was no difference between DFX and DFO in safety evaluation (RR 1.53 with 95%CI 0.31 to 7.49). CONCLUSION Findings indicated that the most effective and safe iron chelators remains to be proven, and further large-scale, long-term studies are needed.
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Affiliation(s)
- Sujian Xia
- Division of Medical Statistics, School of Medicine, University of Jinan, Guangzhou City, Guangdong, China
| | | | - Liting Huang
- Zhuhai People’s Hospital, Zhuhai City, Guangdong, China
- *
| | - Hong Jiang
- Division of Medical Statistics, School of Medicine, University of Jinan, Guangzhou City, Guangdong, China
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Fisher SA, Brunskill SJ, Doree C, Chowdhury O, Gooding S, Roberts DJ. Oral deferiprone for iron chelation in people with thalassaemia. Cochrane Database Syst Rev 2013:CD004839. [PMID: 23966105 DOI: 10.1002/14651858.cd004839.pub3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Thalassaemia major is a genetic disease characterised by a reduced ability to produce haemoglobin. Management of the resulting anaemia is through red blood cell transfusions.Repeated transfusions result in an excessive accumulation of iron in the body (iron overload), removal of which is achieved through iron chelation therapy. A commonly used iron chelator, deferiprone, has been found to be pharmacologically efficacious. However, important questions exist about the efficacy and safety of deferiprone compared to another iron chelator, desferrioxamine. OBJECTIVES To summarise data from trials on the clinical efficacy and safety of deferiprone and to compare the clinical efficacy and safety of deferiprone with desferrioxamine for thalassaemia. SEARCH METHODS We searched the Cochrane Cystic fibrosis and Genetic Disorders Group's Haemoglobinopathies trials Register and MEDLINE, EMBASE, CENTRAL (The Cochrane Library), LILACS and other international medical databases, plus registers of ongoing trials and the Transfusion Evidence Library (www.transfusionevidencelibrary.com). We also contacted the manufacturers of deferiprone and desferrioxamine.All searches were updated to 05 March 2013. SELECTION CRITERIA Randomised controlled trials comparing deferiprone with another iron chelator; or comparing two schedules or doses of deferiprone, in people with transfusion-dependent thalassaemia. DATA COLLECTION AND ANALYSIS Two authors independently assessed trials for risk of bias and extracted data. Missing data were requested from the original investigators. MAIN RESULTS A total of 17 trials involving 1061 participants (range 13 to 213 participants per trial) were included. Of these, 16 trials compared either deferiprone alone with desferrioxamine alone, or a combined therapy of deferiprone and desferrioxamine with either deferiprone alone or desferrioxamine alone; one compared different schedules of deferiprone. There was little consistency between outcomes and limited information to fully assess the risk of bias of most of the included trials.Four trials reported mortality; each reported the death of one individual receiving deferiprone with or without desferrioxamine. One trial reported five further deaths in patients who withdrew from randomised treatment (deferiprone with or without desferrioxamine) and switched to desferrioxamine alone. Seven trials reported cardiac function or liver fibrosis as measures of end organ damage.Earlier trials measuring the cardiac iron load indirectly by magnetic resonance imaging (MRI) T2* signal had suggested deferiprone may reduce cardiac iron more quickly than desferrioxamine. However, a meta-analysis of two trials suggested that left ventricular ejection fraction was significantly reduced in patients who received desferrioxamine alone compared with combination therapy. One trial, which planned five years of follow up, was stopped early due to the beneficial effects of combined treatment compared with deferiprone alone in terms of serum ferritin levels reduction.The results of this and three other trials suggest an advantage of combined therapy over monotherapy to reduce iron stores as measured by serum ferritin. There is, however, no conclusive or consistent evidence for the improved efficacy of combined deferiprone and desferrioxamine therapy over monotherapy from direct or indirect measures of liver iron. Both deferiprone and desferrioxamine produce a significant reduction in iron stores in transfusion-dependent, iron-overloaded people. There is no evidence from randomised controlled trials to suggest that either has a greater reduction of clinically significant end organ damage.Evidence of adverse events were observed in all treatment groups. Occurrence of any adverse event was significantly more likely with deferiprone than desferrioxamine in one trial, RR 2.24 (95% CI 1.19 to 4.23). Meta-analysis of a further two trials showed a significant increased risk of adverse events associated with combined deferiprone and desferrioxamine compared with desferrioxamine alone, RR 3.04 (95% CI 1.18 to 7.83). The most commonly reported adverse event was joint pain, which occurred significantly more frequently in patients receiving deferiprone than desferrioxamine, RR 2.64 (95% CI 1.21 to 5.77). Other common adverse events included gastrointestinal disturbances as well as neutropenia or leucopenia, or both. AUTHORS' CONCLUSIONS In the absence of data from randomised controlled trials, there is no evidence to suggest the need for a change in current treatment recommendations; namely that deferiprone is indicated for treating iron overload in people with thalassaemia major when desferrioxamine is contraindicated or inadequate. Intensified desferrioxamine treatment (by either subcutaneous or intravenous route) or use of other oral iron chelators, or both, remains the established treatment to reverse cardiac dysfunction due to iron overload. Indeed, the US Food and Drug Administration (FDA) recently only gave support for deferiprone to be used as a last resort for treating iron overload in thalassaemia, myelodysplasia and sickle cell disease. However, there is evidence that adverse events are increased in patients treated with deferiprone compared with desferrioxamine and in patients treated with combined deferiprone and desferrioxamine compared with desferrioxamine alone. There is an urgent need for adequately-powered, high-quality trials comparing the overall clinical efficacy and long-term outcome of deferiprone with desferrioxamine.
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Affiliation(s)
- Sheila A Fisher
- Systematic Review Initiative, NHS Blood and Transplant, Level 2, John Radcliffe Hospital, Headington, Oxford, Oxon, UK, OX3 9BQ
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Fisher SA, Brunskill SJ, Doree C, Gooding S, Chowdhury O, Roberts DJ. Desferrioxamine mesylate for managing transfusional iron overload in people with transfusion-dependent thalassaemia. Cochrane Database Syst Rev 2013:CD004450. [PMID: 23963793 DOI: 10.1002/14651858.cd004450.pub3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Thalassaemia major is a genetic disease characterised by a reduced ability to produce haemoglobin. Management of the resulting anaemia is through red blood cell transfusions.Repeated transfusions result in an excessive accumulation of iron in the body (iron overload), removal of which is achieved through iron chelation therapy. Desferrioxamine mesylate (desferrioxamine) is one of the most widely used iron chelators. Substantial data have shown the beneficial effects of desferrioxamine, although adherence to desferrioxamine therapy is a challenge. Alternative oral iron chelators, deferiprone and deferasirox, are now commonly used. Important questions exist about whether desferrioxamine, as monotherapy or in combination with an oral iron chelator, is the best treatment for iron chelation therapy. OBJECTIVES To determine the effectiveness (dose and method of administration) of desferrioxamine in people with transfusion-dependent thalassaemia.To summarise data from trials on the clinical efficacy and safety of desferrioxamine for thalassaemia and to compare these with deferiprone and deferasirox. SEARCH METHODS We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register. We also searched MEDLINE, EMBASE, CENTRAL (The Cochrane Library), LILACS and other international medical databases, plus ongoing trials registers and the Transfusion Evidence Library (www.transfusionevidencelibrary.com). All searches were updated to 5 March 2013. SELECTION CRITERIA Randomised controlled trials comparing desferrioxamine with placebo, with another iron chelator, or comparing two schedules or doses of desferrioxamine, in people with transfusion-dependent thalassaemia. DATA COLLECTION AND ANALYSIS Six authors working independently were involved in trial quality assessment and data extraction. For one trial, investigators supplied additional data upon request. MAIN RESULTS A total of 22 trials involving 2187 participants (range 11 to 586 people) were included. These trials included eight comparisons between desferrioxamine alone and deferiprone alone; five comparisons between desferrioxamine combined with deferiprone and deferiprone alone; eight comparisons between desferrioxamine alone and desferrioxamine combined with deferiprone; two comparisons of desferrioxamine with deferasirox; and two comparisons of different routes of desferrioxamine administration (bolus versus continuous infusion). Overall, few trials measured the same or long-term outcomes. Seven trials reported cardiac function or liver fibrosis as measures of end organ damage; none of these included a comparison with deferasirox.Five trials reported a total of seven deaths; three in patients who received desferrioxamine alone, two in patients who received desferrioxamine and deferiprone. A further death occurred in a patient who received deferiprone in another who received deferasirox alone. One trial reported five further deaths in patients who withdrew from randomised treatment (deferiprone with or without desferrioxamine) and switched to desferrioxamine alone.One trial planned five years of follow up but was stopped early due to the beneficial effects of a reduction in serum ferritin levels in those receiving combined desferrioxamine and deferiprone treatment compared with deferiprone alone. The results of this and three other trials suggest an advantage of combined therapy with desferrioxamine and deferiprone over monotherapy to reduce iron stores as measured by serum ferritin. There is, however, no evidence for the improved efficacy of combined desferrioxamine and deferiprone therapy against monotherapy from direct or indirect measures of liver iron.Earlier trials measuring the cardiac iron load indirectly by measurement of the magnetic resonance imaging T2* signal had suggested deferiprone may reduce cardiac iron more quickly than desferrioxamine. However, meta-analysis of two trials showed a significantly lower left ventricular ejection fraction in patients who received desferrioxamine alone compared with those who received combination therapy using desferrioxamine with deferiprone.Adverse events were recorded by 18 trials. These occurred with all treatments, but were significantly less likely with desferrioxamine than deferiprone in one trial, relative risk 0.45 (95% confidence interval 0.24 to 0.84) and significantly less likely with desferrioxamine alone than desferrioxamine combined with deferiprone in two other trials, relative risk 0.33 (95% confidence interval 0.13 to 0.84). In particular, four studies reported permanent treatment withdrawal due to adverse events from deferiprone; only one of these reported permanent withdrawals associated with desferrioxamine. Adverse events also occurred at a higher frequency in patients who received deferasirox than desferrioxamine in one trial. Eight trials reported local adverse reactions at the site of desferrioxamine infusion including pain and swelling. Adverse events associated with deferiprone included joint pain, gastrointestinal disturbance, increases in liver enzymes and neutropenia; adverse events associated with deferasirox comprised increases in liver enzymes and renal impairment. Regular monitoring of white cell counts has been recommended for deferiprone and monitoring of liver and renal function for deferasirox.In summary, desferrioxamine and the oral iron chelators deferiprone and deferasirox produce significant reductions in iron stores in transfusion-dependent, iron-overloaded people. There is no evidence from randomised clinical trials to suggest that any one of these has a greater reduction of clinically significant end organ damage, although in two trials, combination therapy with desferrioxamine and deferiprone showed a greater improvement in left ventricular ejection fraction than desferrioxamine used alone. AUTHORS' CONCLUSIONS Desferrioxamine is the recommended first-line therapy for iron overload in people with thalassaemia major and deferiprone or deferasirox are indicated for treating iron overload when desferrioxamine is contraindicated or inadequate. Oral deferasirox has been licensed for use in children aged over six years who receive frequent blood transfusions and in children aged two to five years who receive infrequent blood transfusions. In the absence of randomised controlled trials with long-term follow up, there is no compelling evidence to change this conclusion.Worsening iron deposition in the myocardium in patients receiving desferrioxamine alone would suggest a change of therapy by intensification of desferrioxamine treatment or the use of desferrioxamine and deferiprone combination therapy.Adverse events are increased in patients treated with deferiprone compared with desferrioxamine and in patients treated with combined deferiprone and desferrioxamine compared with desferrioxamine alone. People treated with all chelators must be kept under close medical supervision and treatment with deferiprone or deferasirox requires regular monitoring of neutrophil counts or renal function respectively. There is an urgent need for adequately-powered, high-quality trials comparing the overall clinical efficacy and long-term outcomes of deferiprone, deferasirox and desferrioxamine.
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Affiliation(s)
- Sheila A Fisher
- Systematic Review Initiative, NHS Blood and Transplant, Level 2, John Radcliffe Hospital, Headington, Oxford, Oxon, UK, OX3 9BQ
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Viprakasit V, Nuchprayoon I, Chuansumrit A, Torcharus K, Pongtanakul B, Laothamatas J, Srichairatanakool S, Pooliam J, Supajitkasem S, Suriyaphol P, Tanphaichitr VS, Tuchinda S. Deferiprone (GPO-L-ONE(®) ) monotherapy reduces iron overload in transfusion-dependent thalassemias: 1-year results from a multicenter prospective, single arm, open label, dose escalating phase III pediatric study (GPO-L-ONE; A001) from Thailand. Am J Hematol 2013; 88:251-60. [PMID: 23460233 DOI: 10.1002/ajh.23386] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/19/2012] [Accepted: 12/24/2012] [Indexed: 01/19/2023]
Abstract
Accessibility to iron chelators including deferoxamine and deferasirox remains obscured in many developing countries. To provide an alternative, the government pharmaceutical organization of Thailand (GPO) manufactured deferiprone which has similar bioequivalent to the standard product. Seventy-three pediatric patients with severe β thalassemias, age range 3.2-19 years, were recruited to a 1-year multicenter prospective, single arm, open label, dose escalating Phase III study of deferiprone to determine its clinical efficacy and safety. Sixty-four patients (87.6%) completed the study with good compliance (>94%). Average deferiprone dose was 79.1±4.3 mg/kg/day. Overall, mean serum ferritin (SF) levels at 1 year were not significantly changed from baseline. However, 45% of patients (response group) had SF reduced >15% from baseline at 1 year with a median reduction of 1,065 ng ml(-1) . Baseline SF was the major factor that predicts clinical efficacy; patients with baseline SF>3,500 ng ml(-1) had the most significant fall of SF at 1 year. A subgroup analysis by MRI-T2* confirmed that the response group had higher baseline liver iron and deferiprone could significantly reduce liver iron overload and normalize levels of ALT at 1 year. Although, gastrointestinal irritation (20.5%) was the most common drug-related adverse events (AEs) followed by transaminitis (16.4%) and neutropenia (6.8%), all patients were well tolerated. There was no mortality and agranulocytosis found in this trial. Monotherapy of deferiprone with appropriate dose adjustment and monitoring for adverse events appeared to be an effective chelation therapy in some patients with good compliance and acceptable safety profiles.
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Affiliation(s)
- Vip Viprakasit
- Hematology/Oncology Division, Department of Pediatrics and Thalassemia Center; Faculty of Medicine Siriraj Hospital, Mahidol University; Bangkok Thailand
| | - Issarang Nuchprayoon
- Department of Pediatrics; King Chulalongkorn Memorial Hospital, Chulalongkorn University; Bangkok Thailand
| | - Ampaiwan Chuansumrit
- Department of Pediatrics; Ramathibodi Hospital, Mahidol University; Bangkok Thailand
| | - Kitti Torcharus
- Department of Pediatrics; Phramongkutklao College of Medicine; Bangkok Thailand
| | - Bunchoo Pongtanakul
- Hematology/Oncology Division, Department of Pediatrics and Thalassemia Center; Faculty of Medicine Siriraj Hospital, Mahidol University; Bangkok Thailand
| | - Jiraporn Laothamatas
- Department of Radiology; Ramathibodi Hospital, Mahidol University; Bangkok Thailand
| | - Somdet Srichairatanakool
- Department of Biochemistry; Faculty of Medicine; Chiang Mai University; Chiang Mai, Bangkok Thailand
| | - Julaporn Pooliam
- Clinical Epidemiology Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital; Mahidol University; Bangkok Thailand
| | - Siriwat Supajitkasem
- Bioinformatics and Data Management for Research Unit; Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University; Bangkok Thailand
| | - Prapat Suriyaphol
- Bioinformatics and Data Management for Research Unit; Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University; Bangkok Thailand
| | - Voravarn S. Tanphaichitr
- Hematology/Oncology Division, Department of Pediatrics and Thalassemia Center; Faculty of Medicine Siriraj Hospital, Mahidol University; Bangkok Thailand
- Thalassemia Foundation of Thailand (TFT); Bangkok Thailand
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Iron chelation therapy in thalassemia major: A systematic review with meta-analyses of 1520 patients included on randomized clinical trials. Blood Cells Mol Dis 2011; 47:166-75. [DOI: 10.1016/j.bcmd.2011.07.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2011] [Revised: 07/02/2011] [Accepted: 07/03/2011] [Indexed: 01/19/2023]
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Porter JB, Shah FT. Iron overload in thalassemia and related conditions: therapeutic goals and assessment of response to chelation therapies. Hematol Oncol Clin North Am 2011; 24:1109-30. [PMID: 21075283 DOI: 10.1016/j.hoc.2010.08.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Transfusional iron loading inevitably results in hepatic iron accumulation, with variable extrahepatic distribution that is typically less pronounced in sickle cell disease than in thalassemia disorders. Iron chelation therapy has the goal of preventing iron-mediated tissue damage through controlling tissue iron levels, without incurring chelator-mediated toxicity. Historically, target levels for tissue iron control have been limited by the increased frequency of deferoxamine-mediated toxicity and low levels of iron loading. With newer chelation regimes, these limitations are less evident. The reporting of responses to chelation therapies has typically focused on average changes in serum ferritin in patient populations. This approach has three limitations. First, changes in serum ferritin may not reflect trends in iron balance equally in all patients or for all chelation regimens. Second, this provides no information about the proportion of patients likely respond. Third, this gives insufficient information about iron trends in tissues such as the heart. Monitoring of iron overload has advanced with the increasing use of MRI techniques to estimate iron balance (changes in liver iron concentration) and extrahepatic iron distribution (myocardial T2*). The term nonresponder has been increasingly used to describe individuals who fail to show a downward trend in one or more of these variables. Lack of a response of an individual may result from inadequate dosing, high transfusion requirement, poor treatment adherence, or unfavorable pharmacology of the chelation regime. This article scrutinizes evidence for response rates to deferoxamine, deferiprone (and combinations), and deferasirox.
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Affiliation(s)
- John B Porter
- Red Cell Disorders Unit, University College London Hospital, 250 Euston Road, London, UK.
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Clinical efficacy and safety evaluation of tailoring iron chelation practice in thalassaemia patients from Asia-Pacific: a subanalysis of the EPIC study of deferasirox. Int J Hematol 2011; 93:319-328. [PMID: 21374076 DOI: 10.1007/s12185-011-0789-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 02/08/2011] [Accepted: 02/09/2011] [Indexed: 10/18/2022]
Abstract
Although thalassaemia is highly prevalent in the Asia-Pacific region, clinical data on efficacy and safety profiles of deferasirox in patients from this region are rather limited. Recently, data from the multicentre Evaluation of Patients' Iron Chelation with Exjade (EPIC) study in 1744 patients with different anaemias has provided an opportunity to analyse 1115 thalassaemia patients, of whom 444 patients were from five countries in the Asia-Pacific region (AP) for whom thalassaemia management and choice of iron chelators were similar. Compared to the rest of the world (ROW), baseline clinical data showed that the AP group appeared to be more loaded with iron (3745.0 vs. 2822.0 ng/ml) and had a higher proportion on deferoxamine monotherapy prior to the study (82.9 vs. 58.9%). Using a starting deferasirox dose based on transfusional iron intake and tailoring it to individual patient response, clinical efficacy based on serum ferritin reduction in AP and ROW thalassaemia patients was similar. Interestingly, the AP group developed a higher incidence of drug-related skin rash compared to ROW (18.0 vs. 7.2%), which may indicate different pharmacogenetic backgrounds in the two populations. Our analysis confirms that, with appropriate adjustment of dose, deferasirox can be clinically effective across different regions, with manageable side effects.
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Ha SY, Mok ASP, Chu WCW, Raskalkar DD, Cheuk DKL, Chiang AKS, Ho MHK, Chan GCF. A Practical Chelation Protocol Based on Stratification of Thalassemic Patients by Serum Ferritin and Magnetic Resonance Imaging Cardiac T2*. Hemoglobin 2009; 33:323-31. [DOI: 10.3109/03630260903211979] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Maggio A, Vitrano A, Capra M, Cuccia L, Gagliardotto F, Filosa A, Romeo MA, Magnano C, Caruso V, Argento C, Gerardi C, Campisi S, Violi P, Malizia R, Cianciulli P, Rizzo M, D’Ascola DG, Quota A, Prossomariti L, Fidone C, Rigano P, Pepe A, D’Amico G, Morabito A, Gluud C. Long-term sequential deferiprone-deferoxamineversusdeferiprone alone for thalassaemia major patients: a randomized clinical trial. Br J Haematol 2009; 145:245-54. [DOI: 10.1111/j.1365-2141.2009.07609.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Roberts DJ, Brunskill SJ, Doree C, Williams S, Howard J, Hyde CJ. Oral deferiprone for iron chelation in people with thalassaemia. Cochrane Database Syst Rev 2007:CD004839. [PMID: 17636775 DOI: 10.1002/14651858.cd004839.pub2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Thalassaemia major is a genetic disease characterised by a reduced ability to produce haemoglobin. Management of the resulting anaemia is through transfusions of red blood cells. Repeated transfusions result in excessive accumulation of iron in the body (iron overload), removal of which is achieved through iron chelation therapy. A commonly used iron chelator, deferiprone, has been found to be pharmacologically efficacious. However, important questions exist about the efficacy and safety of deferiprone compared to another iron chelator, desferrioxamine. OBJECTIVES To summarise data from trials on the clinical efficacy and safety of deferiprone and to compare the clinical efficacy and safety of deferiprone for thalassaemia with desferrioxamine. SEARCH STRATEGY We searched the Group's Haemoglobinopathies Trials Register, MEDLINE, EMBASE, Biological Abstracts, ZETOC, Current Controlled Trials and bibliographies of relevant publications. We contacted the manufacturers of deferiprone and desferrioxamine. Most recent searches: June 2006. SELECTION CRITERIA Randomised controlled trials comparing deferiprone with another iron chelator; or comparing two schedules of deferiprone, in people with transfusion-dependent thalassaemia. DATA COLLECTION AND ANALYSIS Two authors independently assessed trial quality and extracted data. Missing data were requested from the original investigators. MAIN RESULTS Ten trials involving 398 people (range 10 to 144 people) were included. Nine trials compared deferiprone with desferrioxamine or a combination of deferiprone and desferrioxamine and one compared different schedules of deferiprone. There was little consistency between outcomes and little information to fully assess the methodological quality of most of the included trials. No trial reported long-term outcomes (mortality and end organ damage). There was no consistent effect on reduction of iron overload between all treatment comparisons, with the exception of urinary iron excretion in comparisons of deferiprone with desferrioxamine. An increase in iron excretion levels favoured deferiprone in one trial and desferrioxamine in three trials, even though measurement of urinary iron excretion underestimates total iron excretion by desferrioxamine.Adverse events were recorded in trials comparing deferiprone with desferrioxamine. There was evidence of adverse events in all treatment groups. Adverse events in one trial were significantly more likely with deferiprone than desferrioxamine, relative risk 2.24 (95% confidence interval 1.19 to 4.23). AUTHORS' CONCLUSIONS We found no reason to change current treatment recommendations, namely deferiprone is indicated for treating iron overload in people with thalassaemia major when desferrioxamine is contraindicated or inadequate. However, there is an urgent need for adequately-powered, high quality trials comparing the overall clinical efficacy and long-term outcome of deferiprone with desferrioxamine.
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Affiliation(s)
- D J Roberts
- National Blood Service, Systematic Review Initiative, Level 2, John Radcliffe Hospital, Headley Way, Oxford, Oxon, UK, OX3 9BQ.
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Bernhardt PV. Coordination chemistry and biology of chelators for the treatment of iron overload disorders. Dalton Trans 2007:3214-20. [PMID: 17893764 DOI: 10.1039/b708133b] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Treatment of the medical condition generally referred to as iron overload through the delivery of chelators has recently received a major boost. In 2005 Novartis gained FDA approval for the drug deferasirox, which may be taken orally. Until this time most patients with Fe overload have had to endure long periods of subcutaneous infusions of the orally ineffective drug desferrioxamine (desferal) which has led to major problems with patient compliance. An effective Fe chelator must possess a number of properties for it to be able to complex Fe in vivo and be excreted intact. This Perspective will provide an overview of the current state of chelators for Fe overload; both those currently approved and those undergoing preclinical development.
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Affiliation(s)
- Paul V Bernhardt
- Centre for Metals in Biology, Department of Chemistry, University of Queensland, Brisbane, 4072, Australia.
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