Post-mortem study of the association between cardiac iron and fibrosis in transfusion dependent anaemia.

BACKGROUND: Heart failure related to cardiac siderosis remains a major cause of death in transfusion dependent anaemias. Replacement fibrosis has been reported as causative of heart failure in siderotic cardiomyopathy in historical reports, but these findings do not accord with the reversible nature of siderotic heart failure achievable with intensive iron chelation. METHODS: Ten whole human hearts (9 beta-thalassemia major, 1 sideroblastic anaemia) were examined for iron loading and fibrosis (replacement and interstitial). Five had died from heart failure, 4 had cardiac transplantation for heart failure, and 1 had no heart failure (death from a stroke). Heart samples iron content was measured using atomic emission spectroscopy. Interstitial fibrosis was quantified by computer using picrosirius red (PSR) staining and expressed as collagen volume fraction (CVF) with normal value for left ventricle <3%. RESULTS: The 9 hearts affected by heart failure had severe iron loading with very low T2* of 5.0 ± 2.0 ms (iron concentration 8.5 ± 7.0 mg/g dw) and diffuse granular myocardial iron deposition. In none of the 10 hearts was significant macroscopic replacement fibrosis present. In only 2 hearts was interstitial fibrosis present, but with low CVF: in one patient with no cardiac siderosis (death by stroke, CVF 5.9%) and in a heart failure patient (CVF 2%). In the remaining 8 patients, no interstitial fibrosis was seen despite all having severe cardiac siderosis and heart failure (CVF 1.86% ±0.87%). CONCLUSION: Replacement cardiac fibrosis was not seen in the 9 post-mortem hearts from patients with severe cardiac siderosis and heart failure leading to death or transplantation, which contrasts markedly to historical reports. Minor interstitial fibrosis was also unusual and very limited in extent. These findings accord with the potential for reversibility of heart failure seen in iron overload cardiomyopathy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00520559.

Second international round robin for the quantification of serum non-transferrin-bound iron and labile plasma iron in patients with iron-overload disorders.

Non-transferrin-bound iron and its labile (redox active) plasma iron component are thought to be potentially toxic forms of iron originally identified in the serum of patients with iron overload. We compared ten worldwide leading assays (6 for non-transferrin-bound iron and 4 for labile plasma iron) as part of an international inter-laboratory study. Serum samples from 60 patients with four different iron-overload disorders in various treatment phases were coded and sent in duplicate for analysis to five different laboratories worldwide. Some laboratories provided multiple assays. Overall, highest assay levels were observed for patients with untreated hereditary hemochromatosis and ß-thalassemia intermedia, patients with transfusion-dependent myelodysplastic syndromes and patients with transfusion-dependent and chelated ß-thalassemia major. Absolute levels differed considerably between assays and were lower for labile plasma iron than for non-transferrin-bound iron. Four assays also reported negative values. Assays were reproducible with high between-sample and low within-sample variation. Assays correlated and correlations were highest within the group of non-transferrin-bound iron assays and within that of labile plasma iron assays. Increased transferrin saturation, but not ferritin, was a good indicator of the presence of forms of circulating non-transferrin-bound iron. The possibility of using non-transferrin-bound iron and labile plasma iron measures as clinical indicators of overt iron overload and/or of treatment efficacy would largely depend on the rigorous validation and standardization of assays.

IFNL3 polymorphisms and HCV infection in patients with beta thalassemia.

UNLABELLED: BACKGROUND AND RATIONALE FOR THE STUDY: Genome-wide association studies have identified host genetic variation to be critical for spontaneous clearance and treatment response in patients infected with hepatitis C virus. Recently, the role of the IFNL3 polymorphisms in influencing the spontaneous clearance of HCV, the response to interferon and the progression of liver fibrosis, was also demonstrated in patients with thalassemia major infected by genotype 1b. In the present study we retrospectively analyzed 368 anti-HCV positive patients with beta-thalassemia at two Italian major centers in Cagliari and Torino. RESULTS: C/C variant of polymorphism rs12979860 was related to response to interferon treatment and, above all, to spontaneous clearance of the virus. However, the positive predictive power was stronger for viral persistence than spontaneous clearance and in such respect the TT allele was more predictive than CC. The methylation associated polymorphism rs4803221 had independent effects with respect to rs12979860 and the haplotype tagged by SNP rs12979860 and rs4803221 significantly could improve the viral clearance prediction in infected patients. Neither necroinflammation or bilirubin values in the chronic phase of the hepatitis C were related to IFNL3 polymorphisms. No relation among IFNL3 polymorphisms and fibrosis stage directly shown by the liver biopsy was found. CONCLUSIONS: Also in thalassemia the SNPs on chromosome 19q13 closely associates with spontaneous and treatment-induced HCV clearance. The viral clearance prediction is significantly improved by the haplotype tagged by SNP rs12979860 and rs4803221. Neither necroinflammation, bilirubin values or fibrosis stage seem to be related to IFNL3 polymorphisms.

Efficacy and safety of deferiprone for the treatment of pantothenate kinase-associated neurodegeneration (PKAN) and neurodegeneration with brain iron accumulation (NBIA): results from a four years follow-up.

OBJECTIVE: To evaluate the long-term effect of Deferiprone (DFP) in reducing brain iron overload and improving neurological manifestations in patients with NBIA. METHODS: 6 NBIA patients (5 with genetically confirmed PKAN), received DFP solution at 15 mg/kg po bid. They were assessed by UPDRS/III and UDRS scales and blinded video rating, performed at baseline and every six months. All patients underwent brain MRI at baseline and during follow up. Quantitative assessment of brain iron was performed with T2* relaxometry, using a gradient multi-echo T2* sequence. RESULTS: After 48 months of treatment clinical rating scales and blinded video rating indicated a stabilization in motor symptoms in 5/6 Pts. In the same subjects MRI evaluation showed reduced hypointensity in the globus pallidus (GP); quantitative assessment confirmed a significant increment in the T2* value, and hence reduction of the iron content of the GP. CONCLUSION: The data from our 4-years follow-up study confirm the safety of DFP as a chelator agent for iron accumulation. The clinical stabilization observed in 5/6 of our patients suggests that DFP may be a reasonable therapeutic option for the treatment of the neurological manifestations linked with iron accumulation and neurodegeneration, especially in adult patients at early stage of the disease. (Clinicaltrials.gov identifier: NTC00907283).

Deferasirox effectively reduces iron overload in non-transfusion-dependent thalassemia (NTDT) patients: 1-year extension results from the THALASSA study.

Patients with non-transfusion-dependent thalassemia (NTDT) often develop iron overload that requires chelation to levels below the threshold associated with complications. This can take several years in patients with high iron burden, highlighting the value of long-term chelation data. Here, we report the 1-year extension of the THALASSA trial assessing deferasirox in NTDT; patients continued with deferasirox or crossed from placebo to deferasirox. Of 133 patients entering extension, 130 completed. Liver iron concentration (LIC) continued to decrease with deferasirox over 2 years; mean change was -7.14 mg Fe/g dry weight (dw) (mean dose 9.8 ± 3.6 mg/kg/day). In patients originally randomized to placebo, whose LIC had increased by the end of the core study, LIC decreased in the extension with deferasirox with a mean change of -6.66 mg Fe/g dw (baseline to month 24; mean dose in extension 13.7 ± 4.6 mg/kg/day). Of 166 patients enrolled, 64 (38.6 %) and 24 (14.5 %) patients achieved LIC <5 and <3 mg Fe/g dw by the end of the study, respectively. Mean LIC reduction was greatest in patients with the highest pretreatment LIC. Deferasirox progressively decreases iron overload over 2 years in NTDT patients with both low and high LIC. Safety profile of deferasirox over 2 years was consistent with that in the core study.

Deferasirox demonstrates a dose-dependent reduction in liver iron concentration and consistent efficacy across subgroups of non-transfusion-dependent thalassemia patients.

The 1-year THALASSA study enrolled 166 patients with various non-transfusion-dependent thalassemia (NTDT) syndromes, degrees of iron burden and patient characteristics, and demonstrated the overall efficacy and safety of deferasirox in reducing liver iron concentration (LIC) in these patients. Here, reduction in LIC with deferasirox 5 and 10 mg/kg/day starting dose groups is shown to be consistent across the following patient subgroups-baseline LIC/serum ferritin, age, gender, race, splenectomy (yes/no), and underlying NTDT syndrome (ß-thalassemia intermedia, HbE/ß-thalassemia or α-thalassemia). These analyses also evaluated deferasirox dosing strategies for patients with NTDT. Greater reductions in LIC were achieved in patients dose-escalated at Week 24 from deferasirox 10 mg/kg/day starting dose to 20 mg/kg/day. Patients who received an average actual dose of deferasirox >12.5-≤17.5 mg/kg/day achieved a greater LIC decrease compared with the ≥7.5-≤12.5 mg/kg/day and >0-<7.5 mg/kg/day subgroups, demonstrating a dose-response efficacy. LIC reduction across patient subgroups was generally consistent with the primary efficacy analysis with a similar safety profile.

Assessment and management of iron overload in ß-thalassaemia major patients during the 21st century: a real-life experience from the Italian WEBTHAL project.

We conducted a cross-sectional study on 924 ß-thalassaemia major patients (mean age 30·1 years) treated at nine Italian centres using the WEBTHAL software, to evaluate real-life application of iron overload assessment and management standards. Serum ferritin <2500 ng/ml was a risk factor for never having liver iron concentration (LIC) measurement, while absence of cardiac disease and siderosis were risk factors for a delay in LIC measurement >2 years. Patients who never had a cardiac MRI (CMR) T2* measurement were <18 years, had iron intake ≤0·4 mg/kg per day, or a serum ferritin <2500 ng/ml. A history of normal CMR T2* was the main risk factor for a delay in subsequent assessment of >2 years. Deferoxamine (22·8%) was more commonly used in patients with Hepatitis C Virus or high serum creatinine. Deferiprone (20·6%) was less commonly prescribed in patients with elevated alanine aminotransferase; while a deferoxamine + deferiprone combination (17·9%) was more commonly used in patients with serum ferritin >2500 ng/ml or CMR T2* <20 ms. Deferasirox (38·3%) was more commonly prescribed in patients <18 years, but less commonly used in those with heart disease or high iron intake. These observations largely echoed guidelines at the time, although some practices are expected to change in light of evolving evidence.

Brazilian Thalassemia Association protocol for iron chelation therapy in patients under regular transfusion.

In the absence of an iron chelating agent, patients with beta-thalassemia on regular transfusions present complications of transfusion-related iron overload. Without iron chelation therapy, heart disease is the major cause of death; however, hepatic and endocrine complications also occur. Currently there are three iron chelating agents available for continuous use in patients with thalassemia on regular transfusions (desferrioxamine, deferiprone, and deferasirox) providing good results in reducing cardiac, hepatic and endocrine toxicity. These practice guidelines, prepared by the Scientific Committee of Associação Brasileira de Thalassemia (ABRASTA), presents a review of the literature regarding iron overload assessment (by imaging and laboratory exams) and the role of T2* magnetic resonance imaging (MRI) to control iron overload and iron chelation therapy, with evidence-based recommendations for each clinical situation. Based on this review, the authors propose an iron chelation protocol for patients with thalassemia under regular transfusions.

Brazilian Thalassemia Association protocol for iron chelation therapy in patients under regular transfusion

In the absence of an iron chelating agent, patients with beta-thalassemia on regular transfusions present complications of transfusion-related iron overload. Without iron chelation therapy, heart disease is the major cause of death; however, hepatic and endocrine complications also occur. Currently there are three iron chelating agents available for continuous use in patients with thalassemia on regular transfusions (desferrioxamine, deferiprone, and deferasirox) providing good results in reducing cardiac, hepatic and endocrine toxicity. These practice guidelines, prepared by the Scientific Committee of Associação Brasileira de Thalassemia (ABRASTA), presents a review of the literature regarding iron overload assessment (by imaging and laboratory exams) and the role of T2* magnetic resonance imaging (MRI) to control iron overload and iron chelation therapy, with evidence-based recommendations for each clinical situation. Based on this review, the authors propose an iron chelation protocol for patients with thalassemia under regular transfusions.

Deferasirox reduces iron overload significantly in nontransfusion-dependent thalassemia: 1-year results from a prospective, randomized, double-blind, placebo-controlled study.

Nontransfusion-dependent thalassemia (NTDT) patients may develop iron overload and its associated complications despite receiving only occasional or no transfusions. The present 1-year, randomized, double-blind, placebo-controlled THALASSA (Assessment of Exjade in Nontransfusion-Dependent Thalassemia) trial assessed the efficacy and safety of deferasirox in iron-overloaded NTDT patients. A total of 166 patients were randomized in a 2:1:2:1 ratio to starting doses of 5 or 10 mg/kg/d of deferasirox or placebo. The means ± SD of the actual deferasirox doses received over the duration of the study in the 5 and 10 mg/kg/d starting dose cohorts were 5.7 ± 1.4 and 11.5 ± 2.9 mg/kg/d, respectively. At 1 year, the liver iron concentration (LIC) decreased significantly compared with placebo (least-squares mean [LSM] ± SEM, -2.33 ± 0.7 mg Fe/g dry weight [dw], P = .001, and -4.18 ± 0.69 mg Fe/g dw, P < .001) for the 5 and 10 mg/kg/d deferasirox groups, respectively (baseline values [means ± SD], 13.11 ± 7.29 and 14.56 ± 7.92 mg Fe/g dw, respectively). Similarly, serum ferritin decreased significantly compared with placebo by LSM -235 and -337 ng/mL for the deferasirox 5 and 10 mg/kg/d groups, respectively (P < .001). In the placebo patients, LIC and serum ferritin increased from baseline by 0.38 mg Fe/g dw and 115 ng/mL (LSM), respectively. The most common drug-related adverse events were nausea (n = 11; 6.6%), rash (n = 8; 4.8%), and diarrhea (n = 6; 3.6%). This is the first randomized study showing that iron chelation with deferasirox significantly reduces iron overload in NTDT patients with a frequency of overall adverse events similar to placebo.

A phase 2 study of the safety, tolerability, and pharmacodynamics of FBS0701, a novel oral iron chelator, in transfusional iron overload.

This was a 24-week, multicenter phase-2 study designed to assess safety, tolerability, and pharmacodynamics of FBS0701, a novel oral chelator, in adults with transfusional iron overload. Fifty-one patients, stratified by transfusional iron intake, were randomized to FBS0701 at either 14.5 or 29 mg/kg/d (16 and 32 mg/kg/d salt form). FBS0701 was generally well tolerated at both doses. Forty-nine patients (96%) completed the study. There were no drug-related serious adverse events. No adverse events (AEs) showed dose-dependency in frequency or severity. Treatment-related nausea, vomiting, abdominal pain, and diarrhea were each noted in < 5% of patients. Mean serum creatinine did not change significantly from Baseline or between dose groups. Transaminases wer increased in 8 (16%), three of whom acquired HCV on-study from a single blood bank while five had an abnormal baseline ALT. The 24 week mean change in liver iron concentration (ΔLIC) at 14.5 mg/kg/d was +3.1 mg/g (dw); 29% achieved a decrease in LIC. Mean ΔLIC at 29 mg/kg/d was -0.3 mg/g (dw); 44% achieved a decrease in LIC (P < .03 for ΔLIC between doses). The safety and tolerability profile at therapeutic doses compare favorably to other oral chelators.

Responsiveness to oral iron and ascorbic acid in a patient with IRIDA.

Mutations in TMPRSS6 gene cause iron-refractory iron deficiency anemia, a rare autosomal recessive disorder characterized by hypochromic microcytic anemia not responsive to oral iron therapy and partially responsive to parenteral iron administration. Here we report a female infant homozygous for a loss of function mutation in TMPRSS6 gene, who responded to oral iron therapy when supplemented with ascorbic acid.

Deferasirox: pharmacokinetics and clinical experience.

INTRODUCTION: Iron overload is an inevitable consequence of transfusion therapy for a variety of underlying anemias. Iron overload, without effective chelation, will lead to significant morbidity and mortality. Deferasirox (Exjade®) is an oral tridentate iron chelator used for reducing iron overload. AREAS COVERED: In addition to the pharmacokinetic and pharmacodynamic profile of deferasirox, this review examines the efficacy and safety data from pivotal studies with deferasirox in iron-overloaded patients with various anemias, including thalassemia, sickle cell disease and myelodysplastic syndromes. A qualitative literature search for deferasirox was performed using PubMed and recent key congress publications (EHA and ASH); key search terms were deferasirox, pharmacokinetic, pharmacodynamic, efficacy and safety. EXPERT OPINION: Based on the current available data, deferasirox treatment is effective with a clinically manageable safety profile although appropriate dosing according to the severity of iron burden and iron intake, together with the careful monitoring of laboratory parameters and adverse events, is recommended. However, despite advances made in the treatment of iron overload, some patients still do not respond adequately to iron chelators, and increased awareness, understanding and further research are still needed.

Effect of deferiprone or deferoxamine on right ventricular function in thalassemia major patients with myocardial iron overload.

BACKGROUND: Thalassaemia major (TM) patients need regular blood transfusions that lead to accumulation of iron and death from heart failure. Deferiprone has been reported to be superior to deferoxamine for the removal of cardiac iron and improvement in left ventricular (LV) function but little is known of their relative effects on the right ventricle (RV), which is being increasingly recognised as an important prognostic factor in cardiomyopathy. Therefore data from a prospective randomised controlled trial (RCT) comparing these chelators was retrospectively analysed to assess the RV responses to these drugs. METHODS: In the RCT, 61 TM patients were randomised to receive either deferiprone or deferoxamine monotherapy, and CMR scans for T2* and cardiac function were obtained. Data were re-analysed for RV volumes and function at baseline, and after 6 and 12 months of treatment. RESULTS: From baseline to 12 months, deferiprone reduced RV end systolic volume (ESV) from 37.7 to 34.2 mL (p=0.008), whilst RV ejection fraction (EF) increased from 69.6 to 72.2% (p=0.001). This was associated with a 27% increase in T2* (p<0.001) and 3.1% increase in LVEF (p<0.001). By contrast, deferoxamine showed no change in RVESV (38.1 to 39.1 mL, p=0.38), or RVEF (70.0 to 69.9%, p=0.93) whereas the T2* increased by 13% (p<0.001), but with no change in LVEF (0.32%; p=0.66). Analysis of between drugs treatment effects, showed significant improvements favouring deferiprone with a mean effect on RVESV of -1.82 mL (p=0.014) and 1.16% for RVEF (p=0.009). Using regression analysis the improvement in RVEF at 12 months was shown to be greater in patients with lower baseline EF values (p<0.001), with a significant difference in RVEF of 3.5% favouring deferiprone over deferoxamine (p=0.012). CONCLUSION: In this retrospective analysis of a prospective RCT, deferiprone monotherapy was superior to deferoxamine for improvement in RVEF and end-systolic volume. This improvement in the RV volumes and function may contribute to the improved cardiac outcomes seen with deferiprone.

Recent advances in ß-thalassemias.

ß-thalassemias are heterogeneous hereditary anemias characterized by a reduced output of ß-globin chains. The disease is most frequent in the temperate regions of the world, where it represents an important health problem. In the last decades, several programs, aimed at controlling the birth rate of thalassemia newborns by screening and prenatal diagnosis of populations with high risk of ß-thalassemia, have been successful accomplished. Bone marrow transplantation has offered a definitive cure for the fraction of patients with available donors. In the same time, steady improvements were made in the traditional clinical management of ß-thalassemia patients. The introduction of the oral iron chelators deferiprone that preferentially chelates hearth iron and the development of novel NMR diagnostic methods has led to reduced morbility, increased survival and improved quality of life. More recently, major advances have being made in the discovery of critical modifier genes, such as Myb and especially BCL11A (B cell lymphoma 11A), a master regulator of HbF (fetal hemoglobin) and hemoglobin switching. Polimorphysms of BCL11A, Myb and γ-globin genes account for most of the variability in the clinical phenotypes in ß-thalassemia and sickle cell anemia patients. Finally, the year 2010 has brought in the first successful experiment of gene therapy in a ß-thalassemia patient, opening up the perspective of a generalized cure for all ß- thalassemia patients.

A pilot trial of deferiprone for neurodegeneration with brain iron accumulation.

Deferiprone was shown to reverse iron deposition in Friedreich's ataxia. This multi-center, unblinded, single-arm pilot study evaluated safety and efficacy of deferiprone for reducing cerebral iron accumulation in neurodegeneration with brain iron accumulation. Four patients with genetically-confirmed pantothenate kinase-associated neurodegeneration, and 2 with parkinsonism and focal dystonia, but inconclusive genetic tests, received 15 mg/kg deferiprone bid. Magnetic resonance imaging and neurological examinations were conducted at baseline, six and 12 months. Chelation treatment caused no apparent hematologic or neurological side effects. Magnetic resonance imaging revealed decreased iron accumulation in the globus pallidus of 2 patients (one with pantothenate kinase-associated neurodegeneration). Clinical rating scales and blinded video rating evaluations documented mild-to-moderate motor improvement in 3 patients (2 with pantothenate kinase-associated neurodegeneration). These results underline the safety and tolerability of deferiprone, and suggest that chelating treatment might be effective in improving neurological manifestations associated with iron accumulation. (Clinicaltrials.gov Identifier: NTC00907283).

On T2* magnetic resonance and cardiac iron.

BACKGROUND: Measurement of myocardial iron is key to the clinical management of patients at risk of siderotic cardiomyopathy. The cardiovascular magnetic resonance relaxation parameter R2* (assessed clinically via its reciprocal, T2*) measured in the ventricular septum is used to assess cardiac iron, but iron calibration and distribution data in humans are limited. METHODS AND RESULTS: Twelve human hearts were studied from transfusion-dependent patients after either death (heart failure, n=7; stroke, n=1) or transplantation for end-stage heart failure (n=4). After cardiovascular magnetic resonance R2* measurement, tissue iron concentration was measured in multiple samples of each heart with inductively coupled plasma atomic emission spectroscopy. Iron distribution throughout the heart showed no systematic variation between segments, but epicardial iron concentration was higher than in the endocardium. The mean ± SD global myocardial iron causing severe heart failure in 10 patients was 5.98 ± 2.42 mg/g dry weight (range, 3.19 to 9.50 mg/g), but in 1 outlier case of heart failure was 25.9 mg/g dry weight. Myocardial ln[R2*] was strongly linearly correlated with ln[Fe] (R²=0.910, P<0.001), leading to [Fe]=45.0×(T2*)⁻¹·²² for the clinical calibration equation with [Fe] in milligrams per gram dry weight and T2* in milliseconds. Midventricular septal iron concentration and R2* were both highly representative of mean global myocardial iron. CONCLUSIONS: These data detail the iron distribution throughout the heart in iron overload and provide calibration in humans for cardiovascular magnetic resonance R2* against myocardial iron concentration. The iron values are of considerable interest in terms of the level of cardiac iron associated with iron-related death and indicate that the heart is more sensitive to iron loading than the liver. The results also validate the current clinical practice of monitoring cardiac iron in vivo by cardiovascular magnetic resonance of the midseptum.