Amal El Beshlawy

OBJECTIVE: The study evaluates the long-term deferasirox treatment of adult and pediatric patients with chronic transfusional iron overload in clinical practice.

METHODS: In this non-interventional study, patients were observed for up to 3 years from initiation of deferasirox treatment both prospectively and retrospectively for up to 1 year prior to enrollment. The primary end points were the proportion of patients with ≥1 notable increase in serum creatinine (SCr), and ≥1 notable increase in alanine aminotransferase (ALT).

RESULTS: Overall, 120 patients were enrolled and 51 completed the study, with a limited 3-year dropout rate of 12.5% due to adverse events (AEs). Increase in SCr > 33% above baseline and the age-adjusted ULN (upper limit of normal) was observed in 14 patients (95%CI, 7.1-19.2). The ALT levels >5 × ULN was observed in 1 patient. Most frequent AEs reported during treatment with deferasirox include gastrointestinal disturbances.

CONCLUSIONS: The long-term treatment with deferasirox was manageable in most transfusion-dependent patients with no unexpected safety findings. Regular monitoring and an adjusted deferasirox dosing strategy per local labels allowed continued iron chelation treatment and control of transfusional iron in the majority of patients on study.

BACKGROUND: Deoxygenated sickle hemoglobin (HbS) polymerization drives the pathophysiology of sickle cell disease. Therefore, direct inhibition of HbS polymerization has potential to favorably modify disease outcomes. Voxelotor is an HbS polymerization inhibitor.

METHODS: In a multicenter, phase 3, double-blind, randomized, placebo-controlled trial, we compared the efficacy and safety of two dose levels of voxelotor (1500 mg and 900 mg, administered orally once daily) with placebo in persons with sickle cell disease. The primary end point was the percentage of participants who had a hemoglobin response, which was defined as an increase of more than 1.0 g per deciliter from baseline at week 24 in the intention-to-treat analysis.

RESULTS: A total of 274 participants were randomly assigned in a 1:1:1 ratio to receive a once-daily oral dose of 1500 mg of voxelotor, 900 mg of voxelotor, or placebo. Most participants had sickle cell anemia (homozygous hemoglobin S or hemoglobin Sβ-thalassemia), and approximately two thirds were receiving hydroxyurea at baseline. In the intention-to-treat analysis, a significantly higher percentage of participants had a hemoglobin response in the 1500-mg voxelotor group (51%; 95% confidence interval [CI], 41 to 61) than in the placebo group (7%; 95% CI, 1 to 12). Anemia worsened between baseline and week 24 in fewer participants in each voxelotor dose group than in those receiving placebo. At week 24, the 1500-mg voxelotor group had significantly greater reductions from baseline in the indirect bilirubin level and percentage of reticulocytes than the placebo group. The percentage of participants with an adverse event that occurred or worsened during the treatment period was similar across the trial groups. Adverse events of at least grade 3 occurred in 26% of the participants in the 1500-mg voxelotor group, 23% in the 900-mg voxelotor group, and 26% in the placebo group. Most adverse events were not related to the trial drug or placebo, as determined by the investigators.

CONCLUSIONS: In this phase 3 randomized, placebo-controlled trial involving participants with sickle cell disease, voxelotor significantly increased hemoglobin levels and reduced markers of hemolysis. These findings are consistent with inhibition of HbS polymerization and indicate a disease-modifying potential. (Funded by Global Blood Therapeutics; HOPE ClinicalTrials.gov number, NCT03036813.).

Thalassemia is a common inherited monogenic disease. It is characterized by chronic hemolysis, ineffective erythropoiesis (IE) and iron overload. Despite advances in transfusion practices and chelation therapy, still many limitations in delivering these standard therapies exist. Challenges of currently available standard care and advances in understanding the underlying pathophysiological mechanisms in thalassemia stimulated research towards development of novel therapeutic targets. Agents reducing IE as Jak 2 inhibitors and Activin II receptor traps are promising and are currently in clinical trials. Other approaches targeting iron dysregulation as mini-hepcidins, exogenous transferrin and erythroferrone inhibitors are in preclinical studies. Gene therapy, a rapidly evolving field, has exhibited remarkable progress in recent years. Studies have focused on β or γ-globin addition, over expression of endogenous γ-globin-activating transcription factors, silencing of γ-globin repressors and genome editing of β-globin mutations or γ-globin repressors. In this article we provide an overview of emerging recent trends in treatment of thalassemia targeting IE, iron dysregulation and novel curative treatments as gene therapy and gene editing.

Advanced liver disease complicated by hepatopulmonary syndrome is a recognized complication of Gaucher disease. Macrophage-targeted, recombinant enzyme replacement therapy is effective in reversing clinical manifestations attributed to the accumulation of glycolipid-laden macrophages but it is not known whether advanced fibrotic features of the disease can be ameliorated. We describe a splenectomized patient with Gaucher disease who developed massive hepatomegaly, cirrhosis of the liver and life-threatening hepatopulmonary syndrome. Treatment with Imiglucerase enzyme replacement therapy resulted in dramatic reversal of hepatopulmonary syndrome and liver disease. Our report suggests that Gaucher disease pathology involving advanced fibrosis and life-threatening complications can be reversed by imiglucerase enzyme therapy.

Synopsis: Effect of imiglucerase enzyme replacement therapy on Hepatopulmonary Syndrome in Gaucher Disease.

Essentials A residual factor VIII synthesis is likely to be protective towards inhibitor (INH) development. Mutation type-inhibitor risk association was explored in 231 patients with severe hemophilia A. A 2-fold increase in INH development for in silico null vs. non-null mutations was found. A 3.5-fold increase in INH risk for antigen negative vs. antigen positive mutations was found.

SUMMARY: Background The type of F8 mutation is the main predictor of inhibitor development in patients with severe hemophilia A. Mutations expected to allow residual synthesis of factor VIII are likely to play a protective role against alloantibody development by inducing immune tolerance. According to the expected full or partial impairment of FVIII synthesis, F8 variants are commonly classified as null and non-null. Objectives To explore the mutation type-inhibitor risk association in a cohort of 231 patients with severe hemophilia A enrolled in the Survey of Inhibitors in Plasma-Product Exposed Toddlers (SIPPET) randomized trial. Methods The genetic defects in these patients, consisting of inversions of intron 22 (n = 110) and intron 1 (n = 6), large deletions (n = 16), and nonsense (n = 38), frameshift (n = 28), missense (n = 19) and splicing (n = 14) variants, of which 34 have been previously unreported, were reclassified according to two additional criteria: the functional effects of missense and splicing alterations as predicted by multiple in silico analyses, and the levels of FVIII antigen in patient plasma. Results A two-fold increase in inhibitor development for in silico null mutations as compared with in silico non-null mutations (hazard ratio [HR] 2.08, 95% confidence interval [CI] 0.84-5.17) and a 3.5-fold increase in inhibitor development for antigen-negative mutations as compared with antigen-positive mutations (HR 3.61, 95% CI 0.89-14.74] were found. Conclusions Our findings confirm an association between the synthesis of minute amounts of FVIII and inhibitor protection, and underline the importance of investigating the residual FVIII antigen levels associated with causative variants in order to understand their clinical relevance.

BACKGROUND: Children with red blood cell disorders may receive regular transfusions from an early age and consequently accumulate iron. Adequate iron chelation therapy can prevent organ damage and delayed growth/development. Deferasirox is indicated for treatment of pediatric patients with chronic iron overload due to transfusional hemosiderosis; however, fewer than 10% of patients in the registration studies were aged 2 to less than 6 years.

PROCEDURE: Deferasirox, a once-daily oral iron chelator, was evaluated in young pediatric patients with transfusional hemosiderosis during the observational 5-year ENTRUST study. Patients aged 2 to less than 6 years at enrollment received deferasirox according to local prescribing information, with the primary objective of evaluating safety, specifically renal and hepatic function. Serum ferritin was observed as a surrogate efficacy parameter.

RESULTS: In total, 267 patients (mean age 3.2 years) predominantly with β-thalassemia (n = 176, 65.9%) were enrolled. Mean ± standard deviation deferasirox dose was 25.8 ± 6.5 mg/kg per day over a median of 59.9 months. A total of 145 patients (54.3%) completed 5 years' treatment. The proportion of patients with two or more consecutive postbaseline measurements (≥7 days apart) of serum creatinine higher than age-adjusted upper limit of normal (ULN) and alanine aminotransferase more than five times the ULN was 4.4% (95% confidence interval [CI]: 2.1-7.9) and 4.0% (95% CI: 1.8-7.4), respectively. Median serum ferritin decreased from 1,702 ng/ml at baseline to 1,127 ng/ml at 5 years. There were no new safety signals.

CONCLUSIONS: Safety and efficacy of deferasirox in young pediatric patients in this long-term, observational study in everyday clinical practice were consistent with the known deferasirox profile.

BACKGROUND: Gaucher disease (GD) is caused by a deficiency in the lysosomal enzyme glucocerebrosidase. Enzyme replacement therapy (ERT) is recommended for clinical improvement.

METHODS: The efficacy and safety of a new imiglucerase, Abcertin, were assessed in 7 Egyptian patients with treatment-naïve type 1 GD. Each patient was administered a biweekly 60 U/kg dose of Abcertin for 6 months. The primary endpoint was the change in hemoglobin concentration. The secondary endpoints were changes from baseline in platelet counts, spleen and liver volumes, biomarker levels, skeletal parameters, and bone mineral density.

RESULTS: The hemoglobin concentration increased by a mean of 1.96 ± 0.91 g/dL (range 1.11-2.80 g/dL) or 20.6% (P = .001). Statistically significant increases in the platelet count and decreases in the spleen volume and biomarker levels were also observed. There were no severe drug-related adverse events. One patient developed anti-imiglucerase antibodies without neutralizing activity.

CONCLUSION: Our study results demonstrate the efficacy and safety of Abcertin in patients with type 1 GD. This suggests that Abcertin can be an alternative ERT option for type 1 GD.

BACKGROUND: In transfusion-dependent anaemias, while absolute serum ferritin levels broadly correlate with liver iron concentration (LIC), relationships between trends in these variables are unclear. These relationships are important because serum ferritin changes are often used to adjust or switch chelation regimens when liver magnetic resonance imaging (MRI) is unavailable.

OBJECTIVES AND METHODS: This post hoc analysis of the EPIC study compared serum ferritin and LIC in 317 patients with transfusion-dependent thalassaemia before and after 1 yr of deferasirox.

RESULTS: Serum ferritin responses (decreases) occurred in 73% of patients, 80% of whom also have decreased LIC. However, 52% of patients without a serum ferritin response did decrease LIC and by >1 mg Fe/g dw (median 3.9) in 77% of cases. Absolute serum ferritin and LIC values correlated significantly only when serum ferritin was <4000 ng/mL (r = 0.59; P < 0.0001) and not at higher levels (≥4000 ng/mL; r = 0.19). Serum ferritin response was accompanied by decreased LIC in 89% and 70% of cases when serum ferritin was <4000 or ≥4000 ng/mL, respectively.

CONCLUSIONS: As serum ferritin non-response was associated with LIC decrease in over half of patients, use of liver MRI may be particularly useful for differentiating true from apparent non-responders to deferasirox based on serum ferritin trends alone.

In Gaucher disease (GD), deficiency of lysosomal acid β-glucosidase results in a broad phenotypic spectrum that is classified into three types based on the absence (type 1 [GD1]) or presence and severity of primary central nervous system involvement (type 2 [GD2], the fulminant neuronopathic form, and type 3 [GD3], the milder chronic neuronopathic form). Enzyme replacement therapy (ERT) with imiglucerase ameliorates and prevents hematological and visceral manifestations in GD1, but data in GD3 are limited to small, single-center series. The effects of imiglucerase ERT on hematological, visceral and growth outcomes (note: ERT is not expected to directly impact neurologic outcomes) were evaluated during the first 5years of treatment in 253 children and adolescents (<18years of age) with GD3 enrolled in the International Collaborative Gaucher Group (ICGG) Gaucher Registry. The vast majority of GBA mutations in this diverse global population consisted of only 2 mutations: L444P (77%) and D409H (7%). At baseline, GD3 patients exhibited early onset of severe hematological and visceral disease and growth failure. During the first year of imiglucerase treatment, hemoglobin levels and platelet counts increased and liver and spleen volumes decreased, leading to marked decreases in the number of patients with moderate or severe anemia, thrombocytopenia, and hepatosplenomegaly. These improvements were maintained through Year 5. There was also acceleration in linear growth as evidenced by increasing height Z-scores. Despite devastating disease at baseline, the probability of surviving for at least 5years after starting imiglucerase was 92%. In this large, multinational cohort of pediatric GD3 patients, imiglucerase ERT provided a life-saving and life-prolonging benefit for patients with GD3, suggesting that, with proper treatment, many such severely affected patients can lead productive lives and contribute to society.

In the phase 3 Study of Eliglustat Tartrate (Genz-112638) in Patients With Gaucher Disease Who Have Reached Therapeutic Goals With Enzyme Replacement Therapy (ENCORE), at 1 year, eliglustat was noninferior to imiglucerase enzyme therapy in maintaining stable platelet counts, hemoglobin concentrations, and spleen and liver volumes. After this primary analysis period, patients entered a long-term extension phase in which all received eliglustat. Duration on eliglustat ranged from 2 to 5 years, depending on timing of enrollment (which spanned 2 years), treatment group to which patients were randomized, and whether they lived in the United States when commercial eliglustat became available. Here we report long-term safety and efficacy of eliglustat for 157 patients who received eliglustat in the ENCORE trial; data are available for 46 patients who received eliglustat for 4 years. Mean hemoglobin concentration, platelet count, and spleen and liver volumes remained stable for up to 4 years. Year to year, all 4 measures remained collectively stable (composite end point relative to baseline values) in ≥85% of patients as well as individually in ≥92%. Mean bone mineral density z scores (lumbar spine and femur) remained stable and were maintained in the healthy reference range throughout. Eliglustat was well tolerated over 4 years; 4 (2.5%) patients withdrew because of adverse events that were considered related to the study drug. No new or long-term safety concerns were identified. Clinical stability assessed by composite and individual measures was maintained in adults with Gaucher disease type 1 treated with eliglustat who remained in the ENCORE trial for up to 4 years. This trial was registered at www.clinicaltrials.gov as #NCT00943111.

BACKGROUND: The development of neutralizing anti-factor VIII alloantibodies (inhibitors) in patients with severe hemophilia A may depend on the concentrate used for replacement therapy.

METHODS: We conducted a randomized trial to assess the incidence of factor VIII inhibitors among patients treated with plasma-derived factor VIII containing von Willebrand factor or recombinant factor VIII. Patients who met the eligibility criteria (male sex, age <6 years, severe hemophilia A, and no previous treatment with any factor VIII concentrate or only minimal treatment with blood components) were included from 42 sites.

RESULTS: Of 303 patients screened, 264 underwent randomization and 251 were analyzed. Inhibitors developed in 76 patients, 50 of whom had high-titer inhibitors (≥5 Bethesda units). Inhibitors developed in 29 of the 125 patients treated with plasma-derived factor VIII (20 patients had high-titer inhibitors) and in 47 of the 126 patients treated with recombinant factor VIII (30 patients had high-titer inhibitors). The cumulative incidence of all inhibitors was 26.8% (95% confidence interval [CI], 18.4 to 35.2) with plasma-derived factor VIII and 44.5% (95% CI, 34.7 to 54.3) with recombinant factor VIII; the cumulative incidence of high-titer inhibitors was 18.6% (95% CI, 11.2 to 26.0) and 28.4% (95% CI, 19.6 to 37.2), respectively. In Cox regression models for the primary end point of all inhibitors, recombinant factor VIII was associated with an 87% higher incidence than plasma-derived factor VIII (hazard ratio, 1.87; 95% CI, 1.17 to 2.96). This association did not change in multivariable analysis. For high-titer inhibitors, the hazard ratio was 1.69 (95% CI, 0.96 to 2.98). When the analysis was restricted to recombinant factor VIII products other than second-generation full-length recombinant factor VIII, effect estimates remained similar for all inhibitors (hazard ratio, 1.98; 95% CI, 0.99 to 3.97) and high-titer inhibitors (hazard ratio, 2.59; 95% CI, 1.11 to 6.00).

CONCLUSIONS: Patients treated with plasma-derived factor VIII containing von Willebrand factor had a lower incidence of inhibitors than those treated with recombinant factor VIII. (Funded by the Angelo Bianchi Bonomi Foundation and others; ClinicalTrials.gov number, NCT01064284; EudraCT number, 2009-011186-88.).

OBJECTIVES: The randomized comparison of deferasirox to deferoxamine for myocardial iron removal in patients with transfusion-dependent anemias (CORDELIA) gave the opportunity to assess relative prevalence and body distribution of iron overload in screened patients.

METHODS: Patients aged ≥ 10 yr with transfusion-dependent anemias from 11 countries were screened. Data were summarized descriptively, overall and across regions.

RESULTS: Among 925 patients (99.1% with β-thalassemia major; 98.5% receiving prior chelation; mean age 19.2 yr), 36.7% had myocardial iron overload (myocardial T2* ≤ 20 ms), 12.1% had low left ventricular ejection fraction. Liver iron concentration (LIC) (mean 25.8 mg Fe/g dw) and serum ferritin (median 3702 ng/mL) were high. Fewer patients in the Middle East (ME; 28.5%) had myocardial T2* ≤ 20 ms vs. patients in the West (45.9%) and Far East (FE, 40.9%). Patients in the West had highest myocardial iron burden, but lowest LIC (26.9% with LIC < 7 mg Fe/g dw) and serum ferritin. Among patients with normal myocardial iron, a higher proportion of patients from the ME and FE had LIC ≥ 15 than < 7 mg Fe/g dw (ME, 56.7% vs. 17.2%; FE, 78.6% vs. 7.8%, respectively), a trend which was less evident in the West (44.6% vs. 33.9%, respectively). Transfusion and chelation practices differed between regions.

CONCLUSIONS: Evidence of substantial myocardial and liver iron burden across regions revealed a need for optimization of effective, convenient iron chelation regimens. Significant regional variation exists in myocardial and liver iron loading that are not well explained; improved understanding of factors contributing to differences in body iron distribution may be of clinical benefit.

Early heart iron overload in beta thalassemia major patients can be quantified through T2* cardiovascular magnetic resonance (CMR). To clarify the value of tissue Doppler imaging (TDI) in early detection of myocardial dysfunction in iron loaded thalassemia patients diagnosed by CMR. Two groups were included in the study; Group I: 69 asymptomatic thalassemia patients (28 females, 41 males), mean age 18.1 ± 7.03 years (range 6-39 years); Group II (n = 41) healthy normal controls matched for age and sex. Serum ferritin and CMR were performed to assess the cardiac siderosis (T2* < 20 ms). Group I was subdivided into two subgroups; Group Ia (n = 26) T2* < 20 ms and Group Ib (n = 43) T2* > 20 ms. Conventional and Doppler echocardiography of LV, RV dimensions and functions and pulmonary artery pressure were evaluated. Right ventricular diastolic function assessed by tricuspid annular E'/A' was positively correlated with T2* value; lower tricuspid E'/A' ratios were correlated with lower T2* values (r = 0.366, P = 0.002). Tricuspid annular A' was significantly higher in group Ia compared to group Ib (16.7 ± 5.2 vs 12.1 ± 4.0 cm/s, P < 0.001). Tricuspid E'/A' < 1 was common in group Ia compared to group Ib (19/26 (73.0) vs 3/43 (6.97%), P < 0.001). By multivariate analysis, right ventricular diastolic dysfunction (tricuspid E'/A' < 1) was associated with serum ferritin and T2* level of the thalassemia patients. TDI is a promising tool for quantitative assessment of myocardial function and early detection of right ventricular diastolic dysfunction in iron loaded beta thalassemia major patients.

Deferasirox (DFX) monotherapy is effective for reducing myocardial and liver iron concentrations (LIC), although some patients may require intensive chelation for a limited duration. HYPERION, an open-label single-arm prospective phase 2 study, evaluated combination DFX-deferoxamine (DFO) in patients with severe transfusional myocardial siderosis (myocardial [m] T2* 5-<10 ms; left ventricular ejection fraction [LVEF] ≥56%) followed by optional switch to DFX monotherapy when achieving mT2* >10 ms. Mean dose was 30.5 mg/kg per day DFX and 36.3 mg/kg per day DFO on a 5-day regimen. Geometric mean mT2* ratios (Gmeanmonth12/24/Gmeanbaseline) were 1.09 and 1.30, respectively, increasing from 7.2 ms at baseline (n = 60) to 7.7 ms at 12 (n = 52) and 9.5 ms at 24 months (n = 36). Patients (17 of 60; 28.3%) achieved mT2* ≥10 ms and ≥10% increase from baseline at month 24; 15 switched to monotherapy during the study based on favorable mT2*. LIC decreased substantially from a baseline of 33.4 to 12.8 mg Fe/g dry weight at month 24 (-52%). LVEF remained stable with no new arrhythmias/cardiac failure. Five patients discontinued with mT2* <5 ms and 1 died (suspected central nervous system infection). Safety was consistent with established monotherapies. Results show clinically meaningful improvements in mT2* in about one-third of patients remaining on treatment at month 24, alongside rapid decreases in LIC in this heavily iron-overloaded, difficult-to-treat population. Combination therapy may be useful when rapid LIC reduction is required, regardless of myocardial iron overload. This trial was registered at www.clinicaltrials.gov as #NCT01254227.

Iron overload is the major cause of morbidity and mortality in transfusion dependent β-thalassemia major patients. There is a sophisticated balance of body iron metabolism of storage and transport which is regulated by several factors including the peptide hepcidin. Hepcidin is the main iron regulatory molecule; it is secreted mainly by the liver and other tissues including monocytes and lymphocytes. Expression of hepcidin in such cells is unclear and has been studied in few reports with controverted result. Peripheral expression of hepcidin was measured using quantitative real time PCR (qRT-PCR) in 50 β-thalassemia major patients, in addition to 20 healthy volunteers as a control group. Hepcidin levels in β-thalassemia major patients showed statistically significant decrease in comparison to the control group, and was correlated to cardiac iron stores (T2*). However, hepcidin level was not different among the patients according to the HCV status or whether splenectomized or not. In conclusion; peripheral expression of hepcidin, in iron overloaded β-thalassemia major patients, is a reflection of hepatic expression. It can be used as a molecular predictor for the severity of cardiac iron overload and can be used as a future target for therapy in β-thalassemia major patients.

Long-term controlled studies are needed to inform on the clinical benefit of chelation therapy for myocardial iron removal in transfusion-dependent beta thalassemia patients. In a 1-year nonrandomized extension to the CORDELIA study, data collected from patients with myocardial siderosis provided additional information on deferasirox or deferoxamine (DFO) efficacy and safety. Myocardial (m)T2* increased from baseline 11.6 to 15.9 ms in patients receiving deferasirox for 24 months (n = 74; geometric mean [Gmean ] ratio of month 24/baseline 1.38 [95% confidence interval 1.28, 1.49]) and from 10.8 to 14.2 ms in those receiving DFO (n = 29; Gmean ratio 1.33 [1.13, 1.55]; P = 0.93 between groups). Improved mT2* with deferasirox was evident across all subgroups evaluated irrespective of baseline myocardial (mT2* < 10 vs. ≥ 10 ms) or liver (LIC <15 vs. ≥15 mg Fe/g dw) iron burden. Mean LVEF was stable and remained within normal limits with deferasirox or DFO. Liver iron concentration decreased from high baseline values of 30.6 ± 18.0 to 14.4 ± 16.6 mg Fe/g dw at month 24 in deferasirox patients and from 36.8 ± 15.6 to 11.0 ± 12.1 mg Fe/g dw in DFO patients. The long-term safety profile of deferasirox or DFO was consistent with previous reports; serious drug-related AEs were reported in 6.8% of deferasirox and 6.9% of DFO patients. Continued treatment of severely iron-overloaded beta thalassemia patients with deferasirox or DFO led to sustained improvements in myocardial iron irrespective of high or low baseline myocardial or liver iron burden, in parallel with substantial improvements in liver iron (Clinicaltrials.gov identifier: NCT00600938).

Randomized comparison data on the efficacy and safety of deferasirox for myocardial iron removal in transfusion dependent patients are lacking. CORDELIA was a prospective, randomized comparison of deferasirox (target dose 40 mg/kg per day) vs subcutaneous deferoxamine (50-60 mg/kg per day for 5-7 days/week) for myocardial iron removal in 197 β-thalassemia major patients with myocardial siderosis (T2* 6-20 milliseconds) and no signs of cardiac dysfunction (mean age, 19.8 years). Primary objective was to demonstrate noninferiority of deferasirox for myocardial iron removal, assessed by changes in myocardial T2* after 1 year using a per-protocol analysis. Geometric mean (Gmean) myocardial T2* improved with deferasirox from 11.2 milliseconds at baseline to 12.6 milliseconds at 1 year (Gmeans ratio, 1.12) and with deferoxamine (11.6 milliseconds to 12.3 milliseconds; Gmeans ratio, 1.07). The between-arm Gmeans ratio was 1.056 (95% confidence interval [CI], 0.998, 1.133). The lower 95% CI boundary was greater than the prespecified margin of 0.9, establishing noninferiority of deferasirox vs deferoxamine (P = .057 for superiority of deferasirox). Left ventricular ejection fraction remained stable in both arms. Frequency of drug-related adverse events was comparable between deferasirox (35.4%) and deferoxamine (30.8%). CORDELIA demonstrated the noninferiority of deferasirox compared with deferoxamine for myocardial iron removal. This trial is registered at www.clinicaltrials.gov as #NCT00600938.

Myocardial siderosis in thalassemia major remains the leading cause of death in developing countries. Once heart failure develops, the outlook is usually poor with precipitous deterioration and death. Cardiovascular magnetic resonance (CMR) can measure cardiac iron deposition directly using the magnetic relaxation time T2*. This allows earlier diagnosis and treatment and helps to reduce mortality from this cardiac affection. This study aims to determine the prevalence of cardiac siderosis in Egyptian patients who are heavily iron loaded and its relation to liver iron concentration, serum ferritin, and left ventricular ejection fraction. Eighty-nine β-thalassemia patients receiving chelation therapy (mean age of 20.8 ± 6.4 years) were recruited in this study. Tissue iron levels were determined by CMR with cardiac T2* and liver R2*. The mean ± standard deviation (range) of cardiac T2* was 28.5 ± 11.7 ms (4.3 to 53.8 ms), the left ventricular ejection fraction (LVEF) was 67.7 ± 4.7 % (55 to 78 %), and the liver iron concentration (LIC) was 26.1 ± 13.4 mg Fe/g dry weight (dw) (1.5 to 56 mg Fe/g dw). The mean serum ferritin was 4,510 ± 2,847 ng/ml (533 to 22,360 ng/ml), and in 83.2 %, the serum ferritin was >2,500 ng/ml. The prevalence of myocardial siderosis (T2* of <20 ms) was 24.7 % (mean age 20.9 ± 7.5 years), with mean T2* of 12.7 ± 4.4 ms, mean LVEF of 68.6 ±5.8 %, mean LIC of 30.9 ± 13 mg Fe/g dw, and median serum ferritin of 4,996 ng/ml. There was no correlation between T2* and age, LVEF, LIC, and serum ferritin (P = 0.65, P = 0.085, P = 0.99, and P = 0.63, respectively). Severe cardiac siderosis (T2* of <10 ms) was present in 7.9 %, with a mean age of 18.4 ± 4.4 years. Although these patients had a mean T2* of 7.8 ± 1.7 ms, the LVEF was 65.1 ± 6.2 %, and only one patient had heart failure (T2* of 4.3 ms and LVEF of 55 %). LIC and serum ferritin results were 29.8 ± 17.0 mg/g and 7,200 ± 6,950 ng/ml, respectively. In this group of severe cardiac siderosis, T2* was also not correlated to age (P = 0.5), LVEF (P = 0.14), LIC (P = 0.97), or serum ferritin (P = 0.82). There was a low prevalence of myocardial siderosis in the Egyptian thalassemia patients in spite of very high serum ferritin and high LIC. T2* is the best test that can identify at-risk patients who can be managed with optimization of their chelation therapy. The possibility of a genetic component for the resistance to cardiac iron loading in our population should be considered.

PURPOSE: Magnetic resonance imaging (MRI)-based techniques for assessing liver iron concentration (LIC) have been limited by single scanner calibration against biopsy. Here, the calibration of spin-density projection-assisted (SDPA) R2-MRI (FerriScan®) in iron-overloaded β-thalassemia patients treated with the iron chelator, deferasirox, for 12 months is validated.

METHODS: SDPA R2-MRI measurements and percutaneous needle liver biopsy samples were obtained from a subgroup of patients (n = 233) from the ESCALATOR trial. Five different makes and models of scanner were used in the study.

RESULTS: LIC, derived from mean of MRI- and biopsy-derived values, ranged from 0.7 to 50.1 mg Fe/g dry weight. Mean fractional differences between SDPA R2-MRI- and biopsy-measured LIC were not significantly different from zero. They were also not significantly different from zero when categorized for each of the Ishak stages of fibrosis and grades of necroinflammation, for subjects aged 3 to <8 versus ≥8 years, or for each scanner model. Upper and lower 95% limits of agreement between SDPA R2-MRI and biopsy LIC measurements were 74 and -71%.

CONCLUSION: The calibration curve appears independent of scanner type, patient age, stage of liver fibrosis, grade of necroinflammation, and use of deferasirox chelation therapy, confirming the clinical usefulness of SDPA R2-MRI for monitoring iron overload.