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1.
N Engl J Med ; 387(22): 2045-2055, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36449420

RESUMO

BACKGROUND: Iron content is increased in the substantia nigra of persons with Parkinson's disease and may contribute to the pathophysiology of the disorder. Early research suggests that the iron chelator deferiprone can reduce nigrostriatal iron content in persons with Parkinson's disease, but its effects on disease progression are unclear. METHODS: We conducted a multicenter, phase 2, randomized, double-blind trial involving participants with newly diagnosed Parkinson's disease who had never received levodopa. Participants were assigned (in a 1:1 ratio) to receive oral deferiprone at a dose of 15 mg per kilogram of body weight twice daily or matched placebo for 36 weeks. Dopaminergic therapy was withheld unless deemed necessary for symptom control. The primary outcome was the change in the total score on the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 260, with higher scores indicating more severe impairment) at 36 weeks. Secondary and exploratory clinical outcomes at up to 40 weeks included measures of motor and nonmotor disability. Brain iron content measured with the use of magnetic resonance imaging was also an exploratory outcome. RESULTS: A total of 372 participants were enrolled; 186 were assigned to receive deferiprone and 186 to receive placebo. Progression of symptoms led to the initiation of dopaminergic therapy in 22.0% of the participants in the deferiprone group and 2.7% of those in the placebo group. The mean MDS-UPDRS total score at baseline was 34.3 in the deferiprone group and 33.2 in the placebo group and increased (worsened) by 15.6 points and 6.3 points, respectively (difference, 9.3 points; 95% confidence interval, 6.3 to 12.2; P<0.001). Nigrostriatal iron content decreased more in the deferiprone group than in the placebo group. The main serious adverse events with deferiprone were agranulocytosis in 2 participants and neutropenia in 3 participants. CONCLUSIONS: In participants with early Parkinson's disease who had never received levodopa and in whom treatment with dopaminergic medications was not planned, deferiprone was associated with worse scores in measures of parkinsonism than those with placebo over a period of 36 weeks. (Funded by the European Union Horizon 2020 program; FAIRPARK-II ClinicalTrials.gov number, NCT02655315.).


Assuntos
Antiparkinsonianos , Deferiprona , Quelantes de Ferro , Ferro , Doença de Parkinson , Substância Negra , Humanos , Deferiprona/administração & dosagem , Deferiprona/efeitos adversos , Deferiprona/farmacologia , Deferiprona/uso terapêutico , Ferro/análise , Ferro/metabolismo , Levodopa/uso terapêutico , Neutropenia/induzido quimicamente , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Substância Negra/química , Substância Negra/diagnóstico por imagem , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Progressão da Doença , Método Duplo-Cego , Administração Oral , Encéfalo/diagnóstico por imagem , Química Encefálica , Dopaminérgicos/administração & dosagem , Dopaminérgicos/efeitos adversos , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/farmacologia , Antiparkinsonianos/uso terapêutico
2.
Blood Cells Mol Dis ; 107: 102859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820707

RESUMO

We conducted a retrospective cohort study on 663 transfusion-dependent ß-thalassemia patients receiving the same iron chelation monotherapy with deferoxamine, deferiprone, or deferasirox for up to 10 years (median age 31.8 years, 49.9 % females). Patients on all three iron chelators had a steady and significant decline in serum ferritin over the 10 years (median deferoxamine: -170.7 ng/mL, P = 0.049, deferiprone: -236.7 ng/mL, P = 0.001; deferasirox: -323.7 ng/mL, P < 0.001) yet had no significant change in liver iron concentration or cardiac T2*; while noting that patients generally had low hepatic and cardiac iron levels at study start. Median absolute, relative, and normalized changes were generally comparable between the three iron chelators. Patients receiving deferasirox had the highest morbidity and mortality-free survival probability among the three chelators, although the difference was only statistically significant when compared with deferoxamine (P = 0.037). On multivariate Cox regression analysis, there was no significant association between iron chelator type and the composite outcome of morbidity or mortality. In a real-world setting, there is comparable long-term iron chelation effectiveness between the three available iron chelators for patients with mild-to-moderate iron overload.


Assuntos
Transfusão de Sangue , Deferasirox , Deferiprona , Desferroxamina , Quelantes de Ferro , Ferro , Piridonas , Talassemia beta , Humanos , Quelantes de Ferro/uso terapêutico , Talassemia beta/mortalidade , Talassemia beta/terapia , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Feminino , Masculino , Adulto , Estudos Retrospectivos , Desferroxamina/uso terapêutico , Deferiprona/uso terapêutico , Ferro/metabolismo , Deferasirox/uso terapêutico , Piridonas/uso terapêutico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/tratamento farmacológico , Benzoatos/uso terapêutico , Ferritinas/sangue , Adolescente , Triazóis/uso terapêutico , Adulto Jovem , Criança , Resultado do Tratamento , Pessoa de Meia-Idade , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Estudos de Coortes
3.
Am J Hematol ; 99(6): 1031-1039, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38429922

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 , Lactente
4.
Pediatr Blood Cancer ; 71(8): e31035, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38753107

RESUMO

In this review, we provide a summary of evidence on iron overload in young children with transfusion-dependent ß-thalassemia (TDT) and explore the ideal timing for intervention. Key data from clinical trials and observational studies of the three available iron chelators deferoxamine, deferiprone, and deferasirox are also evaluated for inclusion of subsets of young children, especially those less than 6 years of age. Evidence on the efficacy and safety of iron chelation therapy for children ≥2 years of age with transfusional iron overload is widely available. New data exploring the risks and benefits of early-start iron chelation in younger patients with minimal iron overload are also emerging.


Assuntos
Transfusão de Sangue , Terapia por Quelação , Quelantes de Ferro , Sobrecarga de Ferro , Talassemia beta , Humanos , Talassemia beta/terapia , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Quelantes de Ferro/uso terapêutico , Criança , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Terapia por Quelação/métodos , Pré-Escolar , Desferroxamina/uso terapêutico , Deferiprona/uso terapêutico , Piridonas/uso terapêutico , Piridonas/efeitos adversos
5.
Acta Haematol ; 147(4): 427-434, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38104534

RESUMO

BACKGROUND: Most patients with lower risk myelodysplastic neoplasms or syndromes (MDSs) become RBC transfusion-dependent, resulting in iron overload, which is associated with an increased oxidative stress state. Iron-chelation therapy is applied to attenuate the toxic effects of this state. Deferiprone (DFP) is an oral iron chelator, which is not commonly used in this patient population, due to safety concerns, mainly agranulocytosis. The purpose of this study was to assess the effect of DFP, on oxidative stress parameters in iron-overloaded RBC transfusion-dependent patients with lower risk MDSs. METHODS: Adult lower risk MDS patients with a cumulative transfusion burden of >20 red blood cell units and evidence of iron overload (serum ferritin >1,000 ng/mL) were included in this study. DFP was administered (100 mg/kg/day) for 4 months. Blood samples for oxidative stress parameters and iron overload parameters were done at baseline and monthly: reactive oxygen species (ROS), phosphatidylserine, reduced glutathione, membrane lipid peroxidation, serum ferritin, and cellular labile iron pool. The primary efficacy variable was ROS. Tolerability and side effects were recorded as well. A paired t test was applied for statistical analyses. RESULTS: Eighteen patients were treated with DFP. ROS significantly decreased in all cell lineages: median decrease of 58.6% in RBC, 33.3% in PMN, and 39.8% in platelets (p < 0.01 for all). Other oxidative stress markers improved: phosphatidylserine decreased by 57.95%, lipid peroxidase decreased by 141.3%, and reduced gluthathione increased by 72.8% (p < 0.01 for all). The iron-overload marker and cellular labile iron pool decreased by 35% in RBCs, 44.3% in PMN, and 46.3% in platelets (p < 0.01 for all). No significant changes were observed in SF levels. There were no events of agranulocytosis. All AEs were grades 1-2. CONCLUSIONS: Herein, we showed preliminary evidence that DFP decreases iron-induced oxidative stress in MDS patients with a good tolerability profile (albeit a short follow-up period). No cases of severe neutropenia or agranulocytosis were reported. The future challenge is to prove that reduction in iron toxicity will eventually be translated into a clinically meaningful improvement.


Assuntos
Deferiprona , Quelantes de Ferro , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Estresse Oxidativo , Humanos , Deferiprona/uso terapêutico , Deferiprona/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/farmacologia , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Piridonas/uso terapêutico , Piridonas/efeitos adversos , Piridonas/administração & dosagem , Idoso de 80 Anos ou mais , Adulto , Israel , Administração Oral , Espécies Reativas de Oxigênio/metabolismo , Transfusão de Eritrócitos , Ferritinas/sangue
6.
J Pediatr Hematol Oncol ; 46(6): e402-e405, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38832436

RESUMO

BACKGROUND: Hemoglobin disorders such as thalassemia major have created an economic burden on the health care system. Iron chelation therapy (ICT) is the most expensive cost component in patients with thalassemia. ICT was administered to reduce the toxic effects of iron overload. This study aims to compare the costs of iron chelators as monotherapy in patients with thalassemia major in Indonesia, specifically in Cipto Faculty of Medicine, Universit. METHODS: This is a retrospective analytical observational study. Data were collected from the thalassemia registry from 2016 to 2019. Patients' age, gender, type of thalassemia, and type of iron chelation were recorded. Complications and total annual costs were evaluated. All thalassemia patients aged ≥2 years who were only receiving monotherapy ICT and had no history of therapy switching were eligible. We excluded subjects who moved out to other facilities or lost to follow-up. RESULTS: From a total of 256 subjects, 249 subjects were included. The median age is 28 years old. Both sexes were represented equally. As many as 96.8% of subjects have thalassemia beta. Deferiprone was the most common iron chelator used (86.7%). Complications were observed in the subjects based on 4-year data collection; most of them were cardiomyopathy, diabetes mellitus, delayed puberty, and malnutrition ( P =0.422; P =0.867; P =0.004; and P =0.125, respectively). Deferiprone had a lower mean annual cost of USD 3581 than deferasirox, which had a cost of USD 6004. CONCLUSIONS: Cardiomyopathy, diabetes mellitus, delayed puberty, and malnutrition were the most common complications found in the study. This study showed that deferiprone should be taken as consideration as a drug of choice to treat iron overload in thalassemia provided by Indonesian national health insurance which is less costly despite the probability of complications found after the treatment was given. Further investigations are required to evaluate contributing factors of complications in thalassemia.


Assuntos
Deferasirox , Deferiprona , Quelantes de Ferro , Humanos , Deferiprona/uso terapêutico , Deferiprona/efeitos adversos , Masculino , Feminino , Deferasirox/efeitos adversos , Deferasirox/uso terapêutico , Deferasirox/economia , Estudos Retrospectivos , Quelantes de Ferro/economia , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/efeitos adversos , Adulto , Adolescente , Criança , Talassemia/economia , Talassemia/tratamento farmacológico , Adulto Jovem , Indonésia , Talassemia beta/tratamento farmacológico , Talassemia beta/economia , Talassemia beta/complicações , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/economia , Sobrecarga de Ferro/etiologia , Pré-Escolar , Terapia por Quelação/economia , Terapia por Quelação/efeitos adversos
7.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731873

RESUMO

The supply and control of iron is essential for all cells and vital for many physiological processes. All functions and activities of iron are expressed in conjunction with iron-binding molecules. For example, natural chelators such as transferrin and chelator-iron complexes such as haem play major roles in iron metabolism and human physiology. Similarly, the mainstay treatments of the most common diseases of iron metabolism, namely iron deficiency anaemia and iron overload, involve many iron-chelator complexes and the iron-chelating drugs deferiprone (L1), deferoxamine (DF) and deferasirox. Endogenous chelators such as citric acid and glutathione and exogenous chelators such as ascorbic acid also play important roles in iron metabolism and iron homeostasis. Recent advances in the treatment of iron deficiency anaemia with effective iron complexes such as the ferric iron tri-maltol complex (feraccru or accrufer) and the effective treatment of transfusional iron overload using L1 and L1/DF combinations have decreased associated mortality and morbidity and also improved the quality of life of millions of patients. Many other chelating drugs such as ciclopirox, dexrazoxane and EDTA are used daily by millions of patients in other diseases. Similarly, many other drugs or their metabolites with iron-chelation capacity such as hydroxyurea, tetracyclines, anthracyclines and aspirin, as well as dietary molecules such as gallic acid, caffeic acid, quercetin, ellagic acid, maltol and many other phytochelators, are known to interact with iron and affect iron metabolism and related diseases. Different interactions are also observed in the presence of essential, xenobiotic, diagnostic and theranostic metal ions competing with iron. Clinical trials using L1 in Parkinson's, Alzheimer's and other neurodegenerative diseases, as well as HIV and other infections, cancer, diabetic nephropathy and anaemia of inflammation, highlight the importance of chelation therapy in many other clinical conditions. The proposed use of iron chelators for modulating ferroptosis signifies a new era in the design of new therapeutic chelation strategies in many other diseases. The introduction of artificial intelligence guidance for optimal chelation therapeutic outcomes in personalised medicine is expected to increase further the impact of chelation in medicine, as well as the survival and quality of life of millions of patients with iron metabolic disorders and also other diseases.


Assuntos
Quelantes de Ferro , Sobrecarga de Ferro , Humanos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/farmacologia , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/metabolismo , Ferro/metabolismo , Animais , Deferiprona/uso terapêutico , Deferiprona/farmacologia
8.
Yeast ; 40(3-4): 143-151, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36755518

RESUMO

In the absence of YFH1, the yeast ortholog of the human FXN gene, budding yeast Saccharomyces cerevisiae experience similar problems to those of cells with Friedreich's ataxia (FRDA). The comparable phenotypic traits consist of impaired respiration, problems in iron homeostasis, decreased oxidative stress tolerance, and diminished iron-sulfur cluster synthesis, rendering yeast of potential use in FRDA modeling and drug trials. Deferiprone, an iron chelator, is one of the long-term studied potential drugs for FRDA, whereas metformin is a biguanide prescribed to treat type 2 diabetes. In the present study, the effects of deferiprone and metformin treatment on the yeast FRDA model are explored via RNA-sequencing analyses. The comparative inquiry of transcriptome data reveals new promising roles for metformin in FRDA treatment since deferiprone and metformin treatments produce overlapping transcriptional and phenotypic responses in YFH1Δ cells. The results revealed that both deferiprone and metformin treatment does not rescue aerobic respiration in YFH1Δ cells, but they alleviate the FRDA phenotype probably by triggering the retrograde mitochondria-to-nucleus signaling.


Assuntos
Diabetes Mellitus Tipo 2 , Ataxia de Friedreich , Metformina , Humanos , Saccharomyces cerevisiae/genética , Deferiprona/farmacologia , Deferiprona/uso terapêutico , Ataxia de Friedreich/tratamento farmacológico , Ataxia de Friedreich/genética , Metformina/farmacologia , Metformina/uso terapêutico , Ferro
9.
Eur J Haematol ; 110(5): 490-497, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36708354

RESUMO

Iron overload is a pathological condition resulting from a congenital impairment of its regulation, increased intestinal iron absorption secondary to bone marrow erythroid hyperplasia, or a chronic transfusional regimen. In normal conditions, intracellular and systemic mechanisms contribute to maintaining iron balance. When this complex homeostatic mechanism fails, an iron overload could be present. Detecting an iron overload is not easy. The gold standard remains the liver biopsy, even if it is invasive and dangerous. Identifying iron using noninvasive techniques allowed a better understanding of the rate of iron overload in different organs, with a low risk for the patient. Estimating serum ferritin (mg/L) is the easiest and, consequently, the most employed diagnostic tool for assessing body iron stores, even if it could be a not specific method. The most common hematological causes of iron overload are myelodysplastic syndromes, sickle cell disease, and thalassemia. In all of these conditions, three drugs have been approved for the treatment of iron overload: deferiprone, deferoxamine, and deferasirox. These chelators have been demonstrated to help lower tissue iron levels and prevent iron overload complications, improving event-free survival (EFS). Nowadays, the decision to start chelation and which chelator to choose remains the joint decision of the clinician and patient.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Humanos , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/uso terapêutico , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/uso terapêutico , Benzoatos/uso terapêutico , Triazóis , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Ferro
10.
BMC Neurol ; 23(1): 134, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37004026

RESUMO

BACKGROUND: Mitochondrial membrane protein-associated neurodegeneration (MPAN) is a rare and devastating disease caused by pathogenic mutations in C19orf12 gene. MPAN is characterized by pathological iron accumulation in the brain and fewer than 100 cases of MPAN have been described. Although the diagnosis of MPAN has achieved a great breakthrough with the application of the whole exome gene sequencing technology, the therapeutic effect of iron chelation therapy in MPAN remains controversial. CASE PRESENTATION: We reported that two sisters from the same family diagnosed with MPAN had dramatically different responses to deferiprone (DFP) treatment. The diagnosis of MPAN were established based on typical clinical manifestations, physical examination, brain magnetic resonance imaging (MRI), cerebrospinal fluid analysis (CSF) and gene sequencing results. The clinical presentations of the two sisters with MPAN due to novel gene locus mutations were similar to those previously reported. There is no other difference in basic information except that the proband had a later onset age and fertility history. Both the proband and his second sister were treated with deferiprone (DFP), but they had dramatically different responses to the treatment. The proband's condition deteriorated sharply after treatment with DFP including psychiatric symptoms and movement disorders. However, the second sister of the proband became relatively stable after receiving the DFP treatment. After four years of follow-up, the patient still denies any new symptoms of neurological deficits. CONCLUSION: The findings of this study enriched the MPAN gene database and indicated that DFP might ameliorate symptom progression in patients without severe autonomic neuropsychiatric impairment at the early stage of the disease.


Assuntos
Proteínas Mitocondriais , Doenças Neurodegenerativas , Humanos , Deferiprona/uso terapêutico , Proteínas Mitocondriais/genética , Doenças Neurodegenerativas/genética , Mutação/genética , Proteínas de Membrana/genética , Ferro
11.
Transfus Apher Sci ; 62(3): 103702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37055329

RESUMO

Drug-induced nephrolithiasis can arise from insoluble components within medications or crystallization of metabolites due to changes in metabolism and urinary pH. The connection between drugs utilized for iron chelation therapy (ICT) and nephrolithiasis is not well understood. In this report, we describe two pediatric patients diagnosed with nephrolithiasis while undergoing treatment with the chelating agents deferasirox, deferiprone, and deferoxamine for iron overload secondary to repeat blood transfusion.


Assuntos
Sobrecarga de Ferro , Nefrolitíase , Talassemia beta , Humanos , Criança , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Deferasirox/efeitos adversos , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Benzoatos/efeitos adversos , Triazóis , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Nefrolitíase/induzido quimicamente , Nefrolitíase/complicações , Nefrolitíase/tratamento farmacológico , Ferro/uso terapêutico , Talassemia beta/terapia
12.
Int J Mol Sci ; 24(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38069073

RESUMO

The design of clinical protocols and the selection of drugs with appropriate posology are critical parameters for therapeutic outcomes. Optimal therapeutic protocols could ideally be designed in all diseases including for millions of patients affected by excess iron deposition (EID) toxicity based on personalised medicine parameters, as well as many variations and limitations. EID is an adverse prognostic factor for all diseases and especially for millions of chronically red-blood-cell-transfused patients. Differences in iron chelation therapy posology cause disappointing results in neurodegenerative diseases at low doses, but lifesaving outcomes in thalassemia major (TM) when using higher doses. In particular, the transformation of TM from a fatal to a chronic disease has been achieved using effective doses of oral deferiprone (L1), which improved compliance and cleared excess toxic iron from the heart associated with increased mortality in TM. Furthermore, effective L1 and L1/deferoxamine combination posology resulted in the complete elimination of EID and the maintenance of normal iron store levels in TM. The selection of effective chelation protocols has been monitored by MRI T2* diagnosis for EID levels in different organs. Millions of other iron-loaded patients with sickle cell anemia, myelodysplasia and haemopoietic stem cell transplantation, or non-iron-loaded categories with EID in different organs could also benefit from such chelation therapy advances. Drawbacks of chelation therapy include drug toxicity in some patients and also the wide use of suboptimal chelation protocols, resulting in ineffective therapies. Drug metabolic effects, and interactions with other metals, drugs and dietary molecules also affected iron chelation therapy. Drug selection and the identification of effective or optimal dose protocols are essential for positive therapeutic outcomes in the use of chelating drugs in TM and other iron-loaded and non-iron-loaded conditions, as well as general iron toxicity.


Assuntos
Sobrecarga de Ferro , Talassemia beta , Humanos , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/efeitos adversos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/induzido quimicamente , Terapia por Quelação/métodos , Ferro/metabolismo , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Quimioterapia Combinada
13.
Br J Haematol ; 199(2): 171-172, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35929529

RESUMO

Transfusion-dependent Diamond-Blackfan anaemia (DBA) patients rapidly develop iron overload and frequently experience cardiac complications. The report by Lecornec and colleagues offers useful details on indications and the management of deferiprone, a highly efficient chelator in removing excess cardiac iron but associated with a high risk of agranulocytosis in DBA patients. Commentary on: Lecornec et al. Agranulocytosis in patients with Diamond-Blackfan anaemia (DBA) treated with deferiprone for post-transfusion iron overload: A retrospective study of the French DBA cohort. British Journal of Haematology 2022;199:285-288.


Assuntos
Agranulocitose , Anemia de Diamond-Blackfan , Sobrecarga de Ferro , Anemia de Diamond-Blackfan/complicações , Anemia de Diamond-Blackfan/terapia , Quelantes , Deferiprona/uso terapêutico , Humanos , Ferro/uso terapêutico , Sobrecarga de Ferro/complicações , Estudos Retrospectivos
14.
Blood ; 136(21): 2457-2468, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32678895

RESUMO

Congenital erythropoietic porphyria (CEP) is an inborn error of heme synthesis resulting from uroporphyrinogen III synthase (UROS) deficiency and the accumulation of nonphysiological porphyrin isomer I metabolites. Clinical features are heterogeneous among patients with CEP but usually combine skin photosensitivity and chronic hemolytic anemia, the severity of which is related to porphyrin overload. Therapeutic options include symptomatic strategies only and are unsatisfactory. One promising approach to treating CEP is to reduce the erythroid production of porphyrins through substrate reduction therapy by inhibiting 5-aminolevulinate synthase 2 (ALAS2), the first and rate-limiting enzyme in the heme biosynthetic pathway. We efficiently reduced porphyrin accumulation after RNA interference-mediated downregulation of ALAS2 in human erythroid cellular models of CEP disease. Taking advantage of the physiological iron-dependent posttranscriptional regulation of ALAS2, we evaluated whether iron chelation with deferiprone could decrease ALAS2 expression and subsequent porphyrin production in vitro and in vivo in a CEP murine model. Treatment with deferiprone of UROS-deficient erythroid cell lines and peripheral blood CD34+-derived erythroid cultures from a patient with CEP inhibited iron-dependent protein ALAS2 and iron-responsive element-binding protein 2 expression and reduced porphyrin production. Furthermore, porphyrin accumulation progressively decreased in red blood cells and urine, and skin photosensitivity in CEP mice treated with deferiprone (1 or 3 mg/mL in drinking water) for 26 weeks was reversed. Hemolysis and iron overload improved upon iron chelation with full correction of anemia in CEP mice treated at the highest dose of deferiprone. Our findings highlight, in both mouse and human models, the therapeutic potential of iron restriction to modulate the phenotype in CEP.


Assuntos
Anemia Hemolítica/tratamento farmacológico , Deferiprona/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Transtornos de Fotossensibilidade/tratamento farmacológico , Porfiria Eritropoética/tratamento farmacológico , 5-Aminolevulinato Sintetase/antagonistas & inibidores , 5-Aminolevulinato Sintetase/biossíntese , 5-Aminolevulinato Sintetase/genética , Adulto , Anemia Hemolítica/etiologia , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Eritroides/efeitos dos fármacos , Células Eritroides/metabolismo , Feminino , Técnicas de Introdução de Genes , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/etiologia , Leucemia Eritroblástica Aguda/patologia , Camundongos , Células-Tronco de Sangue Periférico/efeitos dos fármacos , Células-Tronco de Sangue Periférico/metabolismo , Transtornos de Fotossensibilidade/etiologia , Porfiria Aguda Intermitente/metabolismo , Porfiria Eritropoética/complicações , Porfirinas/biossíntese , Interferência de RNA , RNA Interferente Pequeno/farmacologia
15.
Mov Disord ; 37(9): 1948-1952, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35996824

RESUMO

BACKGROUND: Neuroferritinopathy is a rare inherited neurodegenerative disease with brain iron accumulation characterized by brain iron overload resulting in progressive movement disorders. No treatment is currently available. OBJECTIVE: We assessed conservative iron chelation with deferiprone at 30 mg/kg/day on the disease progression with controlled periods of discontinuation. METHODS: Four patients with confirmed molecular diagnosis of neuroferritinopathy were given deferiprone at different stages of disease progression and with clinical and biological monitoring to control benefit and risk. RESULTS: The four patients showed slight to high improvement. In one case, we managed to stabilize disease progression for more than 11 years. In another case, we were able to reverse symptoms after a few months of treatment. The earliest the treatment was started, the most efficient it was on disease progression. CONCLUSIONS: Conservative iron chelation should be further assessed in neuroferritinopathy. © 2022 International Parkinson and Movement Disorder Society.


Assuntos
Quelantes de Ferro , Doenças Neurodegenerativas , Deferiprona/uso terapêutico , Progressão da Doença , Humanos , Quelantes de Ferro/uso terapêutico , Distúrbios do Metabolismo do Ferro , Distrofias Neuroaxonais , Doenças Neurodegenerativas/tratamento farmacológico , Piridonas/uso terapêutico
16.
Ann Hematol ; 101(3): 533-539, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34981144

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 Jovem
17.
Hemoglobin ; 46(2): 75-80, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35982534

RESUMO

Deferiprone (DFP) is an oral iron-chelating agent that is widely used in thalassemia patients with iron overload. This study aimed to investigate the long-term efficacy of DFP monotherapy on serum ferritin (SF) and adverse events. All thalassemia patients aged 15 years or older who received DFP monotherapy were identified from the thalassemia registry database between November 2008 and October 2019. After treatment, patients who achieved a target SF level, defined as <1000.0 ng/mL in transfusion-dependent thalassemia (TDT) and <800.0 ng/mL in non-TDT (NTDT) for two consecutive visits, were categorized as the achievable group. We used multivariate analysis to identify factors that contribute to differences between groups. One hundred and five patients were enrolled in the study with a median age of 28 (19-41) years and median initial SF level of 1399.0 (1141.0-2169.0) ng/mL. Of these, 61.0% carried Hb E (HBB: c.79G>A)/ß-thalassemia (ß-thal) and 60.0% were TDT patients. The median DFP dose was 63 (47-73) mg/kg/d and the median follow-up duration of treatment was 36 (20-54) months. A total of 58 (55.24%) patients were in the achievable group. The initial SF level <1350.0 ng/mL was significantly associated with achieving a targeted SF level (p = 0.002). Ten adverse events resulted in withholding DFP. The most common was gastrointestinal irritation in four patients and three patients with agranulocytosis. In conclusion, DFP is an effective iron chelator in thalassemia patients. Slightly more than half the patients (55.0%) achieved a target SF level. Lower SF levels at the beginning were an important factor.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Adulto , Humanos , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Ferritinas , Ferro/metabolismo , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Piridonas/efeitos adversos , Sistema de Registros , Talassemia/complicações , Talassemia/tratamento farmacológico
18.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743183

RESUMO

The need for preparing new strategies for the design of emergency drug therapies against COVID-19 and similar diseases in the future is rather urgent, considering the high rate of morbidity and especially mortality associated with COVID-19, which so far has exceeded 18 million lives. Such strategies could be conceived by targeting the causes and also the serious toxic side effects of the diseases, as well as associated biochemical and physiological pathways. Deferiprone (L1) is an EMA- and FDA-approved drug used worldwide for the treatment of iron overload and also other conditions where there are no effective treatments. The multi-potent effects and high safety record of L1 in iron loaded and non-iron loaded categories of patients suggests that L1 could be developed as a "magic bullet" drug against COVID-19 and diseases of similar symptomatology. The mode of action of L1 includes antiviral, antimicrobial, antioxidant, anti-hypoxic and anti-ferroptotic effects, iron buffering interactions with transferrin, iron mobilizing effects from ferritin, macrophages and other cells involved in the immune response and hyperinflammation, as well as many other therapeutic interventions. Similarly, several pharmacological and other characteristics of L1, including extensive tissue distribution and low cost of production, increase the prospect of worldwide availability, as well as many other therapeutic approach strategies involving drug combinations, adjuvant therapies and disease prevention.


Assuntos
Tratamento Farmacológico da COVID-19 , Sobrecarga de Ferro , Adulto , Deferiprona/uso terapêutico , Humanos , Ferro/uso terapêutico , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/etiologia , Piridonas/farmacologia , Piridonas/uso terapêutico
19.
Br J Haematol ; 194(1): 200-210, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33942901

RESUMO

Beta-thalassaemia is an inherited blood disorder characterised by ineffective erythropoiesis and anaemia. Consequently, hepcidin expression is reduced resulting in increased iron absorption and primary iron overload. Hepcidin is under the negative control of transmembrane serine protease 6 (TMPRSS6) via cleavage of haemojuvelin (HJV), a co-receptor for the bone morphogenetic protein (BMP)-mothers against decapentaplegic homologue (SMAD) signalling pathway. Considering the central role of the TMPRSS6/HJV/hepcidin axis in iron homeostasis, the inhibition of TMPRSS6 expression represents a promising therapeutic strategy to increase hepcidin production and ameliorate anaemia and iron overload in ß-thalassaemia. In the present study, we investigated a small interfering RNA (siRNA) conjugate optimised for hepatic targeting of Tmprss6 (SLN124) in ß-thalassaemia mice (Hbbth3/+ ). Two subcutaneous injections of SLN124 (3 mg/kg) were sufficient to normalise hepcidin expression and reduce anaemia. We also observed a significant improvement in erythroid maturation, which was associated with a significant reduction in splenomegaly. Treatment with the iron chelator, deferiprone (DFP), did not impact any of the erythroid parameters. However, the combination of SLN124 with DFP was more effective in reducing hepatic iron overload than either treatment alone. Collectively, we show that the combination therapy can ameliorate several disease symptoms associated with chronic anaemia and iron overload, and therefore represents a promising pharmacological modality for the treatment of ß-thalassaemia and related disorders.


Assuntos
Deferiprona/uso terapêutico , Eritropoese/efeitos dos fármacos , Hepcidinas/biossíntese , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Proteínas de Membrana/antagonistas & inibidores , RNA Interferente Pequeno/uso terapêutico , Talassemia beta/tratamento farmacológico , Acetilgalactosamina/administração & dosagem , Animais , Deferiprona/administração & dosagem , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Perfilação da Expressão Gênica , Hepcidinas/genética , Humanos , Ferro/sangue , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/etiologia , Fígado/metabolismo , Magnésio/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Espécies Reativas de Oxigênio , Serina Endopeptidases/genética , Baço/metabolismo , Baço/ultraestrutura , Zinco/metabolismo , Talassemia beta/complicações , Talassemia beta/metabolismo , Talassemia beta/fisiopatologia
20.
Cerebellum ; 20(3): 454-461, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33409768

RESUMO

Superficial siderosis describes haemosiderin deposition on the surface of the brain. When present on infratentorial structures, it can cause ataxia, sensorineural hearing loss and pyramidal signs. There is no proven treatment and patients experience slow progression of symptoms. Iron-chelating agents have been suggested as a therapeutic option and deferiprone is suited as it crosses the blood-brain barrier. However, deferiprone is reported to have a 1-2% risk of agranulocytosis. We performed a systematic review on treatment of infratentorial superficial siderosis with deferiprone based on PRISMA guidelines. Studies were included if in English or an English language translation was available, were about human subjects and referred to patients with ataxia. Studies were excluded if they did not possess an English translation, included animal studies or did not have ataxia. Studies were excluded if they discussed cerebral amyloid angiopathy or siderosis of other regions. Eleven papers were included. We identified 69 patients. Seventeen patients (25%) discontinued the drug. The most encountered adverse effect was anaemia (21.7%). Neutropaenia was observed in 8.7% and agranulocytosis in 5.8% of patients. Clinically, response varied, and stability or improvement was seen across neurological domains in 6 studies while 5 showed a mixed response. On imaging, 13 (28.9%) patients improved, 24 (53.3%) stabilised and 8 (17.8%) deteriorated. A prospective international centralised register of patients should be developed to inform the design and conduct of a multicentre, placebo-controlled, randomised clinical trial to evaluate the efficacy of deferiprone. The evidence from this systematic review is that deferiprone is a promising intervention.


Assuntos
Deferiprona/uso terapêutico , Quelantes de Ferro/uso terapêutico , Siderose/tratamento farmacológico , Animais , Hemossiderina/metabolismo , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
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