RESUMO
Children with transfusion-dependent thalassemia (TDT) require regular blood transfusions that, without iron-chelation therapy, lead to iron-overload toxicities. Current practice delays chelation therapy (late-start) until reaching iron overload (serum ferritin ≥1000 µg/L) to minimize risks of iron-depletion. Deferiprone's distinct pharmacological properties, including iron-shuttling to transferrin, may reduce risks of iron depletion during mild-to-moderate iron loads and iron overload/toxicity in children with TDT. The early-start deferiprone (START) study evaluated the efficacy/safety of early-start deferiprone in infants/young children with TDT. Sixty-four infants/children recently diagnosed with beta-thalassemia and serum ferritin (SF) between 200 and 600 µg/L were randomly assigned 1:1 to receive deferiprone or placebo for 12 months or until reaching SF-threshold (≥1000 µg/L at two consecutive visits). Deferiprone was initiated at 25 mg/kg/day and increased to 50 mg/kg/day; some recipients' dosages increased to 75 mg/kg/day based on iron levels. The primary endpoint was the proportion of patients ≥SF-threshold by month 12. Monthly transferrin saturation (TSAT) assessment evaluated iron-shuttling. At baseline, there was no significant difference in mean age (deferiprone: 3.03 years, placebo: 2.63 years), SF (deferiprone: 513.8 µg/L, placebo: 451.7 µg/L), or TSAT (deferiprone: 47.98%, placebo: 43.43%) between groups. At month 12, there was no significant difference in growth or adverse event (AE) rates between groups. No deferiprone-treated patients were iron-depleted. At month 12, 66% of patients receiving deferiprone remained below SF threshold versus 39% of placebo (p = .045). Deferiprone-treated patients showed higher TSAT levels and reached ≥60% TSAT threshold faster. Early-start deferiprone was well-tolerated, not associated with iron depletion, and efficacious in reducing iron overload in infants/children with TDT. TSAT results provide the first clinical evidence of deferiprone shuttling iron to transferrin.
Assuntos
Sobrecarga de Ferro , Talassemia beta , Humanos , Criança , Lactente , Pré-Escolar , Ferro , Talassemia beta/tratamento farmacológico , Quelantes de Ferro/efeitos adversos , Transferrina , Ferritinas , Piridonas/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologiaRESUMO
Abstract Introduction Magnetic resonance imaging (MRI) T2* technique is used to assess iron overload in the heart, liver and pancreas of thalassaemic patients. Optimal iron chelation and expected tissue iron response rates remain under investigation. The objective of this study was to analyse serum ferritin and the iron concentration in the heart, liver and pancreas measured by MRI T2*/R2* during regular chelation therapy in a real-world cohort of patients with thalassemia. Methods We evaluated thalassaemic patients ≥ 7 years old undergoing chelation/transfusion therapy by MRI and assessed serum ferritin at baseline and follow-up from 2004-2011. Results We evaluated 136 patients, 92% major thalassaemic, with a median age of 18 years, and median baseline ferritin 2.033ng/ml (range: 59-14,123). Iron overload distribution was: liver (99%), pancreas (74%) and heart (36%). After a median of 1.2 years of follow-up, the iron overload in the myocardium reduced from 2,63 Fe mg/g to 2,05 (p 0.003). The optimal R2* pancreas cut-off was 148 Hertz, achieving 78% sensitivity and 73% specificity. However, when combining the R2* pancreas cut off ≤ 50 Hertz and a ferritin ≤ 1222 ng/ml, we could reach a negative predictive value (NPV) of 98% for cardiac siderosis. Only 28% were undergoing combined chelation at baseline assessment, which increased up to 50% on follow up evaluation. Conclusions Chelation therapy significantly reduced cardiac siderosis in thalassaemic patients. In patients with moderate/severe liver iron concentration undergoing chelation therapy, ferritin levels and myocardium iron improved earlier than the liver siderosis.
Assuntos
Humanos , Criança , Talassemia , Sobrecarga de Ferro , Terapia por QuelaçãoRESUMO
INTRODUCTION: Magnetic resonance imaging (MRI) T2* technique is used to assess iron overload in the heart, liver and pancreas of thalassaemic patients. Optimal iron chelation and expected tissue iron response rates remain under investigation. The objective of this study was to analyse serum ferritin and the iron concentration in the heart, liver and pancreas measured by MRI T2*/R2* during regular chelation therapy in a real-world cohort of patients with thalassemia. METHODS: We evaluated thalassaemic patients ≥ 7 years old undergoing chelation/transfusion therapy by MRI and assessed serum ferritin at baseline and follow-up from 2004-2011. RESULTS: We evaluated 136 patients, 92% major thalassaemic, with a median age of 18 years, and median baseline ferritin 2.033ng/ml (range: 59-14,123). Iron overload distribution was: liver (99%), pancreas (74%) and heart (36%). After a median of 1.2 years of follow-up, the iron overload in the myocardium reduced from 2,63 Fe mg/g to 2,05 (p 0.003). The optimal R2* pancreas cut-off was 148 Hertz, achieving 78% sensitivity and 73% specificity. However, when combining the R2* pancreas cut off ≤ 50 Hertz and a ferritin ≤ 1222 ng/ml, we could reach a negative predictive value (NPV) of 98% for cardiac siderosis. Only 28% were undergoing combined chelation at baseline assessment, which increased up to 50% on follow up evaluation. CONCLUSIONS: Chelation therapy significantly reduced cardiac siderosis in thalassaemic patients. In patients with moderate/severe liver iron concentration undergoing chelation therapy, ferritin levels and myocardium iron improved earlier than the liver siderosis.
RESUMO
Patients with sickle cell disease (SCD) who undergo repeated blood transfusions often develop iron overload. Deferiprone (Ferriprox®) is an oral iron chelator indicated for the treatment of transfusional iron overload due to thalassemia syndromes and has been recently approved as a treatment for iron overload in adult and pediatric patients with SCD and other anemias. The present study aims to characterize the pharmacokinetic (PK) profile of deferiprone (DFP) in adult subjects with SCD. In this phase I, open-label study, subjects with SCD were administered a single 1500 mg dose of DFP. Blood and urine samples were collected for PK assessments of DFP and its main metabolite, deferiprone 3-O-glucuronide (DFP-G). Eight subjects were enrolled and completed the study. Following drug administration, serum levels of DFP and DFP-G rose to maximum concentrations at 1.0 and 2.8 h post-dose, respectively. The half-lives of DFP and DFP-G were 1.5 and 1.6 h, respectively. The majority of administered drug was metabolized and excreted as DFP-G, with less than 4% excreted unchanged in urine up to 10 h post-dose. Subjects received a safety assessment 7 (± 3) days post-dose. Two subjects reported mild adverse events unrelated to the study drug, and no other safety concerns were reported. The PK profile of DFP in SCD subjects is consistent with previous reports in healthy adult volunteers, suggesting no special dosing adjustments are indicated for this population. These findings provide valuable insight for treating iron overload in patients with SCD, who have limited chelation therapy treatment options (trial registration number: NCT01835496, date of registration: April 19, 2013).
Assuntos
Anemia Falciforme/complicações , Deferiprona/farmacocinética , Quelantes de Ferro/farmacocinética , Sobrecarga de Ferro/tratamento farmacológico , Adulto , Anemia Falciforme/terapia , Transfusão de Sangue , Terapia por Quelação/efeitos adversos , Deferiprona/efeitos adversos , Deferiprona/uso terapêutico , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Masculino , Adulto JovemRESUMO
Many people with sickle cell disease (SCD) or other anemias require chronic blood transfusions, which often causes iron overload that requires chelation therapy. The iron chelator deferiprone is frequently used in individuals with thalassemia syndromes, but data in patients with SCD are limited. This open-label study assessed the efficacy and safety of deferiprone in patients with SCD or other anemias receiving chronic transfusion therapy. A total of 228 patients (mean age: 16.9 [range, 3-59] years; 46.9% female) were randomized to receive either oral deferiprone (n = 152) or subcutaneous deferoxamine (n = 76). The primary endpoint was change from baseline at 12 months in liver iron concentration (LIC), assessed by R2* magnetic resonance imaging (MRI). The least squares mean (standard error) change in LIC was -4.04 (0.48) mg/g dry weight for deferiprone vs -4.45 (0.57) mg/g dry weight for deferoxamine, with noninferiority of deferiprone to deferoxamine demonstrated by analysis of covariance (least squares mean difference 0.40 [0.56]; 96.01% confidence interval, -0.76 to 1.57). Noninferiority of deferiprone was also shown for both cardiac T2* MRI and serum ferritin. Rates of overall adverse events (AEs), treatment-related AEs, serious AEs, and AEs leading to withdrawal did not differ significantly between the groups. AEs related to deferiprone treatment included abdominal pain (17.1% of patients), vomiting (14.5%), pyrexia (9.2%), increased alanine transferase (9.2%) and aspartate transferase levels (9.2%), neutropenia (2.6%), and agranulocytosis (0.7%). The efficacy and safety profiles of deferiprone were acceptable and consistent with those seen in patients with transfusion-dependent thalassemia. This trial study was registered at www://clinicaltrials.gov as #NCT02041299.
Assuntos
Anemia Falciforme , Sobrecarga de Ferro , Talassemia , Adolescente , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Transfusão de Sangue , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Masculino , Piridonas/efeitos adversos , Talassemia/complicações , Talassemia/tratamento farmacológico , TransferasesRESUMO
BACKGROUND: Transfusion-dependent haemoglobinopathies require lifelong iron chelation therapy with one of the three iron chelators (deferiprone, deferasirox, or deferoxamine). Deferasirox and deferiprone are the only two oral chelators used in adult patients with transfusion-dependent haemoglobinopathies. To our knowledge, there are no randomised clinical trials comparing deferiprone, a less expensive iron chelator, with deferasirox in paediatric patients. We aimed to show the non-inferiority of deferiprone versus deferasirox. METHODS: DEEP-2 was a phase 3, multicentre, randomised trial in paediatric patients (aged 1 month to 18 years) with transfusion-dependent haemoglobinopathies. The study was done in 21 research hospitals and universities in Italy, Egypt, Greece, Albania, Cyprus, Tunisia, and the UK. Participants were receiving at least 150 mL/kg per year of red blood cells for the past 2 years at the time of enrolment, and were receiving deferoxamine (<100 mg/kg per day) or deferasirox (<40 mg/kg per day; deferasirox is not registered for use in children aged <2 years so only deferoxamine was being used in these patients). Any previous chelation treatment was permitted with a 7-day washout period. Patients were randomly assigned 1:1 to receive orally administered daily deferiprone (75-100 mg/kg per day) or daily deferasirox (20-40 mg/kg per day) administered as dispersible tablets, both with dose adjustment for 12 months, stratified by age (<10 years and ≥10 years) and balanced by country. The primary efficacy endpoint was based on predefined success criteria for changes in serum ferritin concentration (all patients) and cardiac MRI T2-star (T2*; patients aged >10 years) to show non-inferiority of deferiprone versus deferasirox in the per-protocol population, defined as all randomly assigned patients who received the study drugs and had available data for both variables at baseline and after 1 year of treatment, without major protocol violations. Non-inferiority was based on the two-sided 95% CI of the difference in the proportion of patients with treatment success between the two groups and was shown if the lower limit of the two-sided 95% CI was greater than -12·5%. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with EudraCT, 2012-000353-31, and ClinicalTrials.gov, NCT01825512. FINDINGS: 435 patients were enrolled between March 17, 2014, and June 16, 2016, 393 of whom were randomly assigned to a treatment group (194 to the deferiprone group; 199 to the deferasirox group). 352 (90%) of 390 patients had ß-thalassaemia major, 27 (7%) had sickle cell disease, five (1%) had thalassodrepanocytosis, and six (2%) had other haemoglobinopathies. Median follow-up was 379 days (IQR 294-392) for deferiprone and 381 days (350-392) for deferasirox. Non-inferiority of deferiprone versus deferasirox was established (treatment success in 69 [55·2%] of 125 patients assigned deferiprone with primary composite efficacy endpoint data available at baseline and 1 year vs 80 [54·8%] of 146 assigned deferasirox, difference 0·4%; 95% CI -11·9 to 12·6). No significant difference between the groups was shown in the occurrence of serious and drug-related adverse events. Three (2%) cases of reversible agranulocytosis occurred in the 193 patients in the safety analysis in the deferiprone group and two (1%) cases of reversible renal and urinary disorders (one case of each) occurred in the 197 patients in the deferasirox group. Compliance was similar between treatment groups: 183 (95%) of 193 patients in the deferiprone group versus 192 (97%) of 197 patients in the deferisirox group. INTERPRETATION: In paediatric patients with transfusion-dependent haemoglobinopathies, deferiprone was effective and safe in inducing control of iron overload during 12 months of treatment. Considering the need for availability of more chelation treatments in paediatric populations, deferiprone offers a valuable treatment option for this age group. FUNDING: EU Seventh Framework Programme.
Assuntos
Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Transfusão de Eritrócitos/métodos , Hemoglobinopatias/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Administração Oral , Adolescente , Agranulocitose/induzido quimicamente , Agranulocitose/epidemiologia , Albânia/epidemiologia , Anemia Falciforme/terapia , Técnicas de Imagem Cardíaca/métodos , Criança , Pré-Escolar , Chipre/epidemiologia , Deferasirox/administração & dosagem , Deferasirox/economia , Deferiprona/administração & dosagem , Deferiprona/economia , Egito/epidemiologia , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Ferritinas/sangue , Ferritinas/efeitos dos fármacos , Grécia/epidemiologia , Hemoglobinopatias/terapia , Humanos , Lactente , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/economia , Sobrecarga de Ferro/sangue , Itália/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Cooperação do Paciente , Resultado do Tratamento , Tunísia/epidemiologia , Reino Unido/epidemiologia , Doenças Urológicas/induzido quimicamente , Doenças Urológicas/epidemiologia , Talassemia beta/terapiaRESUMO
Iron overload is inevitable in patients who are transfusion dependent. In young children with transfusion-dependent thalassemia (TDT), current practice is to delay the start of iron chelation therapy due to concerns over toxicities, which have been observed when deferoxamine was started too early. However, doing so may increase the risk of iron accumulation that will be manifested as toxicities later in life. This study investigated whether deferiprone, a chelator with a lower affinity for iron than deferoxamine, could postpone transfusional iron overload while maintaining a good safety profile. Recently diagnosed TDT infants (N = 64 their age ranged from 10 to 18 (median 12) months, 54.7% males; receiving ≤6 transfusions; serum ferittin (SF) >400 to < 1000 ng/mL were randomized to "early start deferiprone" (.ES-DFP) at a low dose (50 mg/kg/day) or to "delay chelation" (DC), and remained in the study until their serum ferritin (SF) level reached ≥1000 µg/L. 61 patients continued the study Levels of transferrin saturation (TSAT) and labile plasma iron (LPI) were measured as well. By approximately 6 months postrandomization, 100% of the subjects in DC group had achieved SF > 1000 µg/L and TSAT > 70% compared with none in the ES-DFP group. LPI level > 0.6 µM was observed in 97% vs. 40% of the DS and ES groups, respectively, (P < 0.001). The time to reach SF > 1000 µg/L was delayed by 6 months in the ES-DFP group (P < 0.001) without escalating DFP dose. No unexpected, serious, or severe adverse events were seen in the ES-DFP group.
Assuntos
Terapia por Quelação/métodos , Deferiprona/uso terapêutico , Quelantes de Ferro/uso terapêutico , Talassemia/terapia , Transfusão de Sangue , Deferiprona/efeitos adversos , Feminino , Ferritinas/sangue , Humanos , Lactente , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Masculino , Resultado do TratamentoRESUMO
In the inherited hematologic disorder ß-thalassemia major, patients receive regular, lifelong blood transfusions, which carry excess iron that the body is unable to eliminate. Chelation therapy (deferoxamine, deferiprone, deferasirox or deferoxamine-deferiprone combination) is required to reduce iron accumulation in target organs and the associated morbidity and mortality. Each chelation regimen has a distinct safety/efficacy profile and particular costs associated with its use. This review aims to provide an overview of published cost-utility analyses of currently used chelation regimens, and to comment on the potential relevance of their findings in the USA market, where deferiprone has recently been introduced.
Assuntos
Transfusão de Sangue/economia , Custos de Medicamentos , Quelantes de Ferro/economia , Quelantes de Ferro/uso terapêutico , Talassemia beta/economia , Talassemia beta/terapia , Análise Custo-Benefício , Quimioterapia Combinada , Humanos , Modelos Econômicos , Reação Transfusional , Resultado do Tratamento , Talassemia beta/sangue , Talassemia beta/diagnósticoRESUMO
Apesar da introdução da quelação parenteral de ferro com desferoxamina há mais de trinta anos, 50 por cento dos pacientes com talassemia major morrem antes dos 35 anos de idade, predominantemente por insuficiência cardíaca secundária a sobrecarga de ferro. Embora a desferrioxamina, possa reduzir ou estabilizar o acúmulo de ferro no corpo, um grande número de pacientes não recebe terapia adequada com este quelante devido principalmente à intolerância a um regime que requer administração parenteral prolongada, cinco a sete dias por semana. Para esses pacientes, a deferiprona, um quelante oralmente ativo, surge com uma alternativa de tratamento para o controle da sobrecarga de ferro. Um grande número de estudos clínicos demonstraram a segurança e eficácia da deferiprona. Estima-se que mais de 6 mil pacientes com sobrecarga de ferro já tenham sido tratados com este quelante, com alguns pacientes tomando a droga por mais de dez anos. A quantidade de ferro excretada induzida pela deferiprona é diretamente influenciada pela dose da droga e pelo grau de sobrecarga de ferro do paciente. Recentemente, demonstrou-se que desferrioxamina e deferiprona exibem capacidades quelantes diversas e que, usados simultaneamente ou numa terapia sequencial, promovem uma excreção de ferro adicional ou sinérgica com rápida redução na carga de ferro do corpo. Pela primeira vez é possível considerar esquemas de quelação individualizados baseados nas necessidades individuais de cada paciente
mode of administration which impairs the compliancewith the regime of repeatedly subcutaneous infusions.For these patients, the orally active iron chelatordeferiprone is an attractive alternative to control theoverloaded iron. It has been estimated that more thansix thousands patients have already been treated withdeferiprone, with some of them taking the chelator for10 years or more. The deferiprone-induced ironexcretion is directly related to the dose of deferiproneand the patients iron load. In most of transfusiondependentpatients, a dose of 75 mg/kg/day is sufficientto offset the transfusional iron-load. Recently, it hasbeen demonstrated that desferrioxamine anddeferiprone exhibit different chelating capabilities forthe removal of iron from the various body iron poolsand that the use of both chelators promote an additiveor synergistic iron excretion with rapid reduction inthe body iron load. It now is possible to consider tailormadechelation regimens based on individual patientneeds.
Assuntos
Humanos , Terapia por Quelação , Desferroxamina , TalassemiaRESUMO
BACKGROUND AND OBJECTIVES: Iron-induced cardiac disease remains the main cause of death in patients with thalassemia major, despite chelation therapy with deferoxamine. Deferiprone is an iron chelator that has the potential to be more effective than deferoxamine in removing intracellular iron from the heart. However, to date, no study has been designed to examine the frequency of cardiac complications and survival as the primary outcomes of a comparative study between these two chelators. This retrospective study assessed the survival and the occurrence of cardiac disease in all patients with thalassemia major treated for at least 4 years with deferiprone or deferoxamine at a single center. DESIGN AND METHODS: The patients were, on average, 18.4 years old at the start of the review period and were followed up, on average, for 6 years. At baseline there was no significant difference in the percentage of patients with cardiac disease in the two therapy groups. RESULTS: At the end of the study, cardiac dysfunction, expressed as worsening of pre-existing cardiac abnormality or development of new cardiac disease, was diagnosed in 2 (4%) of the 54 deferiprone-treated patients and in 15 (20%) of the 75 deferoxamine-treated patients, from the first to the last measurement (p = 0.007). The Kaplan Meier analysis of cardiac disease-free survival over the 5-year period was significantly more favorable in the deferiprone group (p = 0.003). INTERPRETATION AND CONCLUSIONS: None of the patients treated with deferiprone died, while 3 of the patients treated with deferoxamine died because of irreversible worsening of their cardiac condition during the study period. Findings from this study suggest that long-term therapy with deferiprone provides a greater cardio-protective effect against the toxicity of iron overload than does subcutaneous deferoxamine. Formal prospective studies are warranted to confirm this effect.