RESUMO
Patients with sickle cell disease (SCD) and other anemias who receive blood transfusions are at risk of organ damage due to transfusional iron overload. Deferiprone is an iron chelator with a well-established safety and efficacy profile that is indicated for the treatment of transfusional iron overload. Here, we report safety data from the large-scale, retrospective Ferriprox® Total Care Registry, which involved all patients with SCD taking deferiprone following the 2011 approval of deferiprone in the United States through August 2020. A total of 634 patients who had initiated deferiprone treatment were included. The mean (SD) duration of deferiprone exposure in the registry was 1.6 (1.6) years (range 0 to 9.7 years). In the overall patient population (N = 634), 64.7% (n = 410) of patients reported a total of 1885 adverse events (AEs). In subgroup analyses, 54.6% (n = 71) of pediatric patients and 67.3% (n = 339) of adult patients reported AEs. The most common AEs reported in patients receiving deferiprone were sickle cell crisis (22.7%), nausea (12.1%), vomiting (8.7%), abdominal discomfort (5.4%), and fatigue (5.4%). Neutropenia was reported in four (0.6%) patients and severe neutropenia/agranulocytosis (defined as absolute neutrophil count <0.5 × 109/L) was reported in two (0.3%) patients. Of patients with evaluable data, all cases of neutropenia and severe neutropenia/agranulocytosis resolved with deferiprone discontinuation. Results from the nearly 10 years of real-world data collected in the Ferriprox® Total Care Registry demonstrate that deferiprone is safe and well tolerated in patients with SCD or other anemias who have transfusional iron overload.
Assuntos
Anemia Falciforme , Deferiprona , Quelantes de Ferro , Sistema de Registros , Humanos , Deferiprona/uso terapêutico , Deferiprona/efeitos adversos , Anemia Falciforme/tratamento farmacológico , Masculino , Criança , Adulto , Feminino , Adolescente , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/administração & dosagem , Estudos Retrospectivos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Pré-Escolar , Adulto Jovem , Pessoa de Meia-Idade , LactenteRESUMO
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
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
BACKGROUND: This review highlights the recent scientific advances that have enabled rational design of novel clinical trials for pantothenate kinase-associated neurodegeneration (PKAN), a rare autosomal recessive neurogenetic disorder associated with progressive neurodegenerative changes and functional impairment. PKAN is caused by genetic variants in the PANK2 gene that result in dysfunction in pantothenate kinase 2 (PANK2) enzyme activity, with consequent disruption of coenzyme A (CoA) synthesis, and subsequent accumulation of brain iron. The clinical phenotype is varied and may include dystonia, rigidity, bradykinesia, postural instability, spasticity, loss of ambulation and ability to communicate, feeding difficulties, psychiatric issues, and cognitive and visual impairment. There are several symptom-targeted treatments, but these do not provide sustained benefit as the disorder progresses. OBJECTIVES: A detailed understanding of the molecular and biochemical pathogenesis of PKAN has opened the door for the design of novel rationally designed therapeutics that target the underlying mechanisms. METHODS: Two large double-blind phase 3 clinical trials have been completed for deferiprone (an iron chelation treatment) and fosmetpantotenate (precursor replacement therapy). A pilot open-label trial of pantethine as a potential precursor replacement strategy has also been completed, and a trial of 4-phosphopantetheine has begun enrollment. Several other compounds have been evaluated in pre-clinical studies, and additional clinical trials may be anticipated. CONCLUSIONS: Experience with these trials has encouraged a critical evaluation of optimal trial designs, as well as the development of PKAN-specific measures to monitor outcomes. PKAN provides a valuable example for understanding targeted drug development and clinical trial design for rare disorders. © 2021 International Parkinson and Movement Disorder Society.
Assuntos
Neurodegeneração Associada a Pantotenato-Quinase , Encéfalo/metabolismo , Humanos , Ferro , Neurodegeneração Associada a Pantotenato-Quinase/tratamento farmacológico , Neurodegeneração Associada a Pantotenato-Quinase/genética , Fenótipo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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
Use of the iron chelator deferiprone for treatment of iron overload in thalassemia patients is associated with concerns over agranulocytosis, which requires weekly absolute neutrophil counts (ANC). Here, we analyze all episodes of agranulocytosis (n = 161) and neutropenia (n = 250) during deferiprone use in clinical trials (CT) and postmarketing surveillance programs (PMSP). Rates of agranulocytosis and neutropenia in CT were 1.5% and 5.5%, respectively. Of the agranulocytosis cases, 61% occurred during the first 6 months of therapy and 78% during the first year. These events appeared to be independent of dose, and occurred three times more often in females than males. Their duration was not significantly shortened by use of G-CSF. No patient with baseline neutropenia (n = 12) developed agranulocytosis during treatment, which raises questions about the validity of prior neutropenia as a contraindication to use. Only 1/7 novel neutropenia cases in CT progressed to agranulocytosis with continued treatment, indicating that neutropenia does not necessarily lead to agranulocytosis. The agranulocytosis fatality rate was 0% in CT and 15/143 (11%) in PMSP. Rechallenge with deferiprone produced agranulocytosis in 75% of patients in whom the event had already occurred, and in 10% with previous neutropenia. Weekly ANC monitoring allows early detection and interruption of therapy, but does not prevent agranulocytosis from occurring. Its relevance appears to decrease after the first year of therapy, when agranulocytosis occurs less often. Based upon analysis of data collected over the past 20 years, it appears that patient education may be the key to minimizing agranulocytosis-associated risks during deferiprone therapy. Am. J. Hematol. 91:1026-1031, 2016. © 2016 The Authors. American Journal of Hematology Published by Wiley Periodicals, Inc.
Assuntos
Agranulocitose/induzido quimicamente , Piridonas/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Ensaios Clínicos como Assunto/estatística & dados numéricos , Deferiprona , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Neutrófilos/citologia , Educação de Pacientes como Assunto , Vigilância de Produtos Comercializados/estatística & dados numéricos , Piridonas/uso terapêutico , Fatores de Risco , Fatores Sexuais , Talassemia/complicações , Adulto JovemRESUMO
AIMS: In light of the growing recognition of renal disease in thalassemia, it is important to understand the impact of renal impairment on the pharmacokinetics of iron chelators. This study evaluated the pharmacokinetics and safety of the iron chelator deferiprone (DFP) in subjects with renal impairment in comparison with healthy volunteers (HVs). METHODS: Thirty-two subjects were categorized into four groups based on degree of renal impairment: none, mild, moderate or severe, as determined by estimated glomerular filtration rate (eGFR). All subjects received a single oral dose of 33 mg kg(-1) DFP, provided serum and urine samples for pharmacokinetic assessment over 24 h and were monitored for safety. RESULTS: Renal clearance of DFP decreased as renal impairment increased. However, based on Cmax , AUC(0,t) and AUC(0,∞), there were no significant group differences in systemic exposure, because less than 4% of the drug was excreted unchanged in the urine. DFP is extensively metabolized to a renally excreted, pharmacologically inactive metabolite, deferiprone 3-O-glucuronide (DFP-G), which exhibited higher Cmax , AUC(0,t), AUC(0,∞) and longer tmax and t1/2 in the renally impaired groups compared with HVs. The Cmax and AUCs of DFP-G increased as eGFR decreased. Overall, 75%-95% of the dose was retrieved in urine, either as DFP or DFP-G, regardless of severity of renal impairment. With respect to safety, DFP was well tolerated. CONCLUSIONS: These data suggest that no adjustment of the DFP dosage regimen in patients with renal impairment is necessary, as there were no significant changes in the systemic exposure to the drug.
Assuntos
Piridonas/farmacocinética , Insuficiência Renal/metabolismo , Administração Oral , Adulto , Idoso , Deferiprona , Feminino , Taxa de Filtração Glomerular , Humanos , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/farmacocinética , Masculino , Pessoa de Meia-Idade , Piridonas/efeitos adversos , Piridonas/sangue , Piridonas/urinaRESUMO
OBJECTIVE: We conducted a 6-month, randomized, double-blind, placebo-controlled study to assess safety, tolerability, and efficacy of deferiprone in Friedreich ataxia (FRDA). METHODS: Seventy-two patients were treated with deferiprone 20, 40, or 60mg/kg/day or placebo, divided into 2 daily doses. Safety was the primary objective; secondary objectives included standardized neurological assessments (Friedreich Ataxia Rating Scale [FARS], International Cooperative Ataxia Rating Scale [ICARS], 9-Hole Peg Test [9HPT], Timed 25-Foot Walk, Low-Contrast Letter Acuity), general functional status (Activities of Daily Living), and cardiac assessments. RESULTS: Deferiprone was well tolerated at 20mg/kg/day, whereas more adverse events occurred in the 40mg/kg/day than in the placebo group. The 60mg/kg/day dose was discontinued due to worsening of ataxia in 2 patients. One patient on deferiprone 20mg/kg/day experienced reversible neutropenia, but none developed agranulocytosis. Deferiprone-treated patients receiving 20 or 40mg/kg/day showed a decline in the left ventricular mass index, compared to an increase in the placebo-treated patients. Patients receiving 20mg/kg/day of deferiprone had no significant change in FARS, similar to the placebo-treated patients, whereas those receiving 40mg/kg/day had worsening in FARS and ICARS scores. The lack of deterioration in the placebo arm impaired the ability to detect any potential protective effect of deferiprone. However, subgroup analyses in patients with less severe disease suggested a benefit of deferiprone 20mg/kg/day on ICARS, FARS, kinetic function, and 9HPT. INTERPRETATION: This study demonstrated an acceptable safety profile of deferiprone at 20mg/kg/day for the treatment of patients with FRDA. Subgroup analyses raise the possibility that, in patients with less severe disease, deferiprone 20mg/kg/day may reduce disease progression, whereas higher doses appear to worsen ataxia.
Assuntos
Ataxia de Friedreich/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Piridonas/uso terapêutico , Adolescente , Adulto , Criança , Deferiprona , Avaliação da Deficiência , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Feminino , Ataxia de Friedreich/sangue , Ataxia de Friedreich/fisiopatologia , Humanos , Masculino , Índice de Gravidade de Doença , Resultado do Tratamento , Função Ventricular Esquerda/fisiologia , Adulto JovemRESUMO
Approximately 6% of patients with thalassemia receiving deferiprone develop neutropenia. Present practice is to monitor absolute neutrophil count (ANC) weekly and to interrupt treatment at the first sign of neutropenia, lest continuation lead to progressive neutrophil reduction. In a 6-month study evaluating the safety and efficacy of a liquid form of deferiprone in 100 children, ANC was initially checked weekly for all patients. For individuals experiencing mild neutropenia, deferiprone was continued but monitoring was increased to daily until resolution. Therapy was to be suspended only if the episode was prolonged or if it worsened. Four patients experienced single episodes of mild neutropenia, and two others each experienced two episodes. All eight episodes resolved within 4-7 d despite continued therapy. (One patient later developed agranulocytosis and had treatment terminated.) This study showed that not all cases of mild neutropenia during deferiprone therapy develop into agranulocytosis, and suggests that many may not be caused by deferiprone. Transient declines in ANC to levels defined as neutropenic are common even in healthy individuals, particularly children; and it could be that the frequent monitoring of ANC mandated during deferiprone therapy may reveal cases of transient neutropenia that would otherwise have gone undetected and resolved on their own without clinical consequences. In patients with thalassemia, several factors increase the probability of a transient fall in ANC. These findings raise the question of whether deferiprone should be routinely stopped in cases of mild neutropenia, provided that such patients have their ANC monitored more frequently during the neutropenic episode.
Assuntos
Quelantes de Ferro/efeitos adversos , Contagem de Leucócitos , Neutropenia/sangue , Neutropenia/etiologia , Neutrófilos , Piridonas/efeitos adversos , Talassemia beta/complicações , Criança , Pré-Escolar , Deferiprona , Feminino , Humanos , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/uso terapêutico , Masculino , Piridonas/administração & dosagem , Piridonas/uso terapêutico , Talassemia beta/tratamento farmacológicoRESUMO
BACKGROUND: A risk associated with the iron chelator deferiprone is the development of neutropenia or agranulocytosis. Accordingly, the product label recommends weekly blood monitoring and immediate interruption of treatment upon detection of an absolute neutrophil count (ANC) <1.5 × 10(9)/L, out of concern that continued therapy might lead to a more severe drop. However, it is uncertain how these recommendations are followed under real-life conditions and, if they are not followed, whether continuation of therapy results in increased incidence of agranulocytosis. PROCEDURE: This non-interventional surveillance program assessed the monitoring of deferiprone therapy in clinical practice. A total of 294 patients with transfusion-dependent anemias received deferiprone, as monotherapy or with another chelator, for up to 1 year. The participating physicians were not given any instructions about treatment and monitoring beyond being referred to the information in the package insert. RESULTS: ANC monitoring was conducted at an average interval of 5 ± 4 weeks, and deferiprone was not always interrupted upon detection of neutropenia. One patient (0.3%) experienced agranulocytosis, and nine others (3%) experienced a total of 11 episodes of neutropenia. All neutropenia episodes resolved; median time to resolution was similar whether or not treatment was interrupted; and no case of neutropenia progressed to agranulocytosis. CONCLUSIONS: These data indicate that less frequent ANC monitoring and continuation of deferiprone therapy during neutropenia are not associated with prolonged neutropenia or with progression to agranulocytosis.
Assuntos
Agranulocitose/prevenção & controle , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Neutropenia/prevenção & controle , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Piridonas/uso terapêutico , Adolescente , Adulto , Agranulocitose/induzido quimicamente , Transfusão de Sangue , Criança , Pré-Escolar , Deferiprona , Feminino , Seguimentos , Humanos , Lactente , Sobrecarga de Ferro/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Neutrófilos , Estudos Prospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Southern China has one of the world's largest population of patients needing transfusions. Transfusion and chelation are not uniformly available and no magnetic resonance imaging (MRI) assessment data exists to date. A total of 153 young ß-thalassemia major (ß-TM) patients were assessed using a validated 1.5T scanner in Hong Kong, People's Republic of China (PRC). Their median age was 13 (range 7 to 30), and most patients were young (22.0% age <10, 73.0% age <15, 88.0% age <18). Erratic health care made estimation of total transfusion and chelation exposure impossible. Despite their early age, 24.0% had severe cardiac hemosiderosis [T2*<10 milliseconds (ms)], at ages as early as 8 years old. Median heart iron was 1.68 mg/g dry weight (range 0.19-7.66) and increased with age (p = 0.017), while liver iron was 22.2 mg/g dry weight (range 3.15 to 39.2). Serum ferritin levels were poor predictors of heart and liver, or pancreatic R* and pituitary R* values. Magnetic resonance imaging scans are needed to screen very young ß-TM patients with immediate risk of premature cardiac death in developing nations and triage them to more intensive treatment. This is particularly important in countries with a large number of patients and limited resources. Our data suggests that in developing countries, there is no lower limit for thalassemia MRI scanning programs.
Assuntos
Sobrecarga de Ferro/diagnóstico , Avaliação das Necessidades/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Talassemia beta/diagnóstico , Adolescente , Adulto , Criança , China/epidemiologia , Ferritinas/sangue , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Hemossiderose/diagnóstico , Hemossiderose/epidemiologia , Humanos , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/terapia , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem , Talassemia beta/epidemiologia , Talassemia beta/terapiaRESUMO
Patients treated with deferiprone for transfusional iron overload may experience idiosyncratic drug-induced neutropenia (IDIN) that may put them at risk of infection. The purpose of this analysis was to examine the rates of severe IDIN and risk of serious infections at different ANC levels in patients treated with deferiprone. Events of severe IDIN (ANC <0.5×109/L) and associated serious infections from clinical trials and postmarketing setting were analyzed by 3 discrete ANC levels: Group 1, 0.2-0.5×109/L; Group 2, 0.1-0.199×109/L; Group 3, <0.1×109/L. In clinical trials, 22 events of severe IDIN were observed (Group 1, n=9; Group 2, n=3; Group 3, n=10); total deferiprone exposure was 1990.26 patient-years; and rates of severe IDIN per 100 patient-years were 0.45 in Group 1, 0.15 in Group 2, and 0.50 in Group 3. All serious infections were in Group 3 (3/10, 30.0%). In the postmarketing setting, 176 events of severe IDIN were reported (Group 1, n=65; Group 2, n=20; Group 3, n=91); total deferiprone exposure was 111,570.24 patient-years; and rates of severe IDIN per 100 patient-years were 0.06 in Group 1, 0.02 in Group 2, and 0.08 in Group 3. Rates of serious infection were 7.7% (n=5/65) in Group 1, 10% (n=2/20) in Group 2, and 13.2% (n=12/91) in Group 3. Our findings suggest that in patients receiving deferiprone, ANC below 0.2×109/L carries a high risk of serious infections, consistent with the recent neutropenia guidelines that agranulocytosis with ANC <0.2×109/L is associated with a high risk of serious infections.
RESUMO
Long-term safety and efficacy data on the iron chelator deferiprone in sickle cell disease (SCD) and other anemias are limited. FIRST-EXT was a 2-year extension study of FIRST (Ferriprox in Patients With Iron Overload in Sickle Cell Disease Trial), a 1-year, randomized noninferiority study of deferiprone vs deferoxamine in these populations. Patients who entered FIRST-EXT continued to receive, or were switched to, deferiprone. Altogether, 134 patients were enrolled in FIRST-EXT (mean age: 16.2 years), with mean (SD) exposure to deferiprone of 2.1 (0.8) years over the 2 studies. The primary end point was safety. Secondary end points were change in liver iron concentration (LIC), cardiac T2∗, serum ferritin (SF), and the proportion of responders (≥20% improvement in efficacy measure). The most common adverse events considered at least possibly related to deferiprone were neutropenia (9.0%) and abdominal pain (7.5%). LIC (mg/g dry weight) decreased over time, with mean (SD) changes from baseline at each time point (year 1, -2.64 [4.64]; year 2, -3.91 [6.38]; year 3, -6.64 [7.72], all P < .0001). Mean SF levels (µg/L) decreased significantly after year 2 (-771, P = .0008) and year 3 (-1016, P = .0420). Responder rates for LIC and SF increased each year (LIC: year 1, 46.5%; year 2, 57.1%; year 3, 66.1%; SF: year 1, 35.2%; year 2, 55.2%; year 3, 70.9%). Cardiac T2∗ remained normal in all patients. In conclusion, long-term therapy with deferiprone was not associated with new safety concerns and led to continued and progressive reduction in iron load in individuals with SCD or other anemias. The trial was registered at www.clinicaltrials.gov as #NCT02443545.
Assuntos
Anemia Falciforme , Sobrecarga de Ferro , Adolescente , Humanos , Anemia Falciforme/terapia , Ferritinas , Ferro/metabolismo , Quelantes de Ferro , Piridonas/efeitos adversosRESUMO
INTRODUCTION: Despite knowledge advances on extramedullary haematopoiesis (EMH) in thalassemic patients, the real picture remains an open issue. OBJECTIVES: To assess EMH prevalence in patients with thalassemia major (TM) and intermedia (TI), to describe magnetic resonance imaging (MRI) findings and to explore clinical risk factors. METHODS: In this cross-sectional study, images and clinical records of 184 consecutive patients with thalassemia who underwent T2* MRI between 2004 and 2011 were reviewed. Association of EMH with survival was investigated for patients with available follow-up charts. RESULTS: EMH was detected in 16/168 (9.5%) patients with TM (aged 19-49 years) and in 3/16 (18.8%) with TI (aged 36-41 years). Most (88%) had paravertebral thoracic and/or abdominal masses. Age was significantly associated with EMH risk (hazard ratio, [HR] 1.10/year; confidence interval [CI]: 1.03-1.18; p-value < 0.001), while lower pancreatic iron content by T2*MRI (HR: 0.94/ms; CI: 0.89-0.99; p-value = 0.049) was a protective factor. Estimated survival rate was superior for EMH-positive (n = 19) when compared to EMH-negative patients (n = 75) (p-value = 0.013). CONCLUSIONS: The prevalence of EMH was 10.3% (19/184), presented mainly as tumoral masses of 3 to 10 cm. Age was a risk factor for EMH development, while lower pancreatic iron might be a protective factor in this cohort.
RESUMO
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
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
Limited data are available on the use of deferiprone in children younger than 10 years of age. This study evaluated the safety and efficacy of a new liquid formulation of deferiprone for the treatment of transfusional iron overload in children 1-10 years old. One hundred children (91 thalassemia major, 8 Hb E-ß thalassemia, and 1 sickle cell disease) were enrolled for a 6-month treatment with deferiprone (50 to 100 mg/kg/d). The safety profile was similar to or better than that reported in earlier studies with deferiprone tablets in older children and adults. No unexpected adverse reactions were observed. Gastrointestinal intolerance (GI) was observed in 11% and an increased serum ALT in 12% of the children. Both events were transient. Mild neutropenia, observed in 6% of patients, did not progress to agranulocytosis and resolved despite continuous deferiprone treatment. Two patients experienced agranulocytosis that resolved without complications upon discontinuation of therapy. Deferiprone use was associated with a significant decline in mean serum ferritin level from 2532±1463 µg/L at baseline to 2176±1144 µg/L (P<0.0005). The results of this study show a favorable benefit/risk ratio of deferiprone oral solution for the treatment of young children with transfusional iron overload.
Assuntos
Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Piridonas/administração & dosagem , Reação Transfusional , Talassemia beta/terapia , Administração Oral , Agranulocitose/induzido quimicamente , Anemia Falciforme/terapia , Química Farmacêutica , Criança , Pré-Escolar , Deferiprona , Feminino , Humanos , Lactente , Quelantes de Ferro/efeitos adversos , Masculino , Piridonas/efeitos adversosRESUMO
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.