Compliance and clinical benefit of deferasirox granule and dispersible tablet formulation in pediatric patients with transfusional iron overload: in a randomized, open-label, multicenter, phase II study.

CALYPSO (NCT02435212), a randomized, open-label, multicenter, phase 2 study evaluated the compliance, clinical benefits, and safety of deferasirox granules and dispersible tablets in pediatric patients with iron overload. Iron chelation therapy-naive and iron chelation therapy-pre-treated patients aged 2 to 0.5 mg/mg; 24.5% and 34.2%), upper respiratory tract infection (28.2% and 29.7%), and pyrexia (26.4% and 23.4%). In iron chelation therapy-naive patients, mean compliance and change from baseline in serum ferritin with both deferasirox formulations were not significantly different. The safety profile was comparable between granule and dispersible tablets formulations, and was consistent with the general safety profile of deferasirox.

Combination chelation therapy.

Combination chelation therapies are considered in transfusion-dependent thalassemia patients for whom monotherapy regimens have failed to achieve iron balance or intensification of iron chelation therapy is required for the rapid reduction of excess iron to avoid permanent organ damage. Combination chelation may provide a more flexible approach for individualizing chelation therapy, thereby improving tolerability, adherence, and quality of life. In principle, iron chelators can be combined with an infinite number of dosing regimens; these involve simultaneous or sequential exposure to the chelators on the same day or alternating the drugs on different days. Clinical studies have established the safety and efficacy of chelation combinations. However, real-life data with combination therapies indicate the significance of compliance for a meaningful reduction in iron overload compared to monotherapies.

Modern management of iron overload in thalassemia major patients guided by MRI techniques: real-world data from a long-term cohort study.

Monitoring liver and cardiac iron stores by magnetic resonance imaging (MRI) enables identifying patients at risk of organ-specific morbidity and better tailoring of iron chelation therapy in thalassemia. Nevertheless, serum ferritin (SF) remains the only tool for monitoring iron status in most resource-poor regions. In this study, we assessed the impact of using MRI techniques to guide iron chelation therapy on iron overload outcomes in a cohort of 99 patients with thalassemia major (TM, mean age at baselines 20.7 ± 6.9 years) followed from 2006 to 2019. We also assessed the ability of SF trends to predict changes in consecutive liver iron concentration (LIC) and cardiac T2* (cT2*) measurements. The most commonly used chelator was deferasirox at baseline (65%) and final (72%) assessments. Overall, patients with safe LIC values (< 7 mg/g dw) increased from 57 to 77%, and safe cT2* values (> 20 ms) increased from 72 to 86%. We obtained the most significant improvement in patients with severe and moderate liver (p = 0.006 and p < 0.001) and cardiac (p < 0.0013 and p < 0.0001) iron overload at baseline. SF trends were in the same direction in 64% of changes in LIC, but only 42% of changes were proportional. Most of the changes in SF (64%) and LIC (61%) could not predict changes in cT2*. Moreover, downward trends in SF and LIC were associated with worsening cardiac iron in 29% and 23.5% of consecutive cT2* measurements. Liver and cardiac MRI-driven oral iron chelation improved the iron status of subjects with TM and demonstrated the importance of using validated MRI techniques in critical clinical decisions.

Changing patterns in the epidemiology of ß-thalassemia.

ß-thalassemia major is an inherited hemoglobinopathy that requires lifelong red blood cell transfusions and iron chelation therapy to prevent complications due to iron overload. Traditionally, ß-thalassemia has been more common in certain regions of the world such as the Mediterranean, Middle East, and Southeast Asia. However, the prevalence of ß-thalassemia is increasing in other regions, including Northern Europe and North America, primarily due to migration. This review summarizes the available data on the changing incidence and prevalence of ß-thalassemia as well as factors influencing disease frequency. The data suggest that the epidemiology of ß-thalassemia is changing: Migration has increased the prevalence of the disease in regions traditionally believed to have a low prevalence, while, at the same time, prevention and screening programs in endemic regions have reduced the number of affected individuals. Various approaches to prevention and screening have been used. Region-specific prevention and treatment programs, customized to align with local healthcare resources and cultural values, have been effective in identifying patients and carriers and providing information and care. Significant challenges remain in universally implementing these programs.

Optimising management of deferasirox therapy for patients with transfusion-dependent thalassaemia and lower-risk myelodysplastic syndromes.

Effective iron chelation therapy is an important part of treatment in patients with transfusion-dependent thalassaemia and lower-risk myelodysplastic syndromes (MDS). Key strategies for optimising iron chelation therapy include ensuring good adherence and preventing and managing adverse events (AEs). Good adherence to iron chelation therapy with deferoxamine and deferasirox has been linked to improved survival and/or reductions in complications related to iron overload; however, maintaining good adherence to iron chelators can be challenging. Patients with transfusion-dependent thalassaemia or lower-risk MDS showed better adherence to the deferasirox film-coated tablet (FCT) formulation than to the deferasirox dispersible tablet formulation in the ECLIPSE trial, reflecting in part the improved palatability and convenience of deferasirox FCT. As well as affecting adherence, AEs may lead to dose reduction, interruption or discontinuation, resulting in suboptimal iron chelation therapy. Preventing and successfully managing AEs may help limit their impact on adherence, and following dosage and administration recommendations for iron chelators such as deferasirox may help minimise AEs and optimise treatment in patients with transfusion-dependent thalassaemia and lower-risk MDS.

Iron Chelation Therapy as a Modality of Management.

Introduction of MRI techniques for identifying and monitoring tissue iron overload and the current understanding of iron homeostasis in transfusion-dependent (TDT) and non-transfusion-dependent thalassemia have allowed for a more robust administration of iron chelation therapies. The development of safe and efficient oral iron chelators and the insights gained from large-scale prospective studies using these agents have improved iron overload management. A significant reduction in iron toxicity-induced morbidity and mortality and improvements in quality of life were observed in TDT. The appropriate management of tissue-specific iron loading in TDT has been portrayed using evidence-based data obtained from investigational studies.

Safety and pharmacokinetics of the oral iron chelator SP-420 in ß-thalassemia.

Our phase I, open-label, multi-center, dose-escalation study evaluated the pharmacokinetics (PK) of SP-420, a tridentate oral iron chelating agent of the desferrithiocin class, in patients with transfusion dependent ß-thalassemia. SP-420 was administered as a single dose of 1.5 (n = 3), 3 (n = 3), 6 (n = 3), 12 (n = 3), and 24 (n = 6) mg/kg or as a twice-daily dose of 9 mg/kg (n = 6) over 14-28 days. There was a near dose-linear increase in the mean plasma SP-420 concentrations and in the mean values for Cmax and AUC0-τ over the dose range evaluated. The median tmax ranged from 0.5 to 2.25 h and was not dose dependent. The study was prematurely terminated by the sponsor due to renal adverse events (AE) including proteinuria, increase in serum creatinine, and one case of Fanconi syndrome. Other adverse effects included hypersensitivity reactions and gastrointestinal disturbances. Based on current dose administration, the renal AE observed outweighed the possible benefits from chelation therapy. However, additional studies assessing efficacy and safety of lower doses or less frequent dosing of SP-420 over longer durations with close monitoring would be necessary to better explain the findings of our study and characterize the safety of the study drug.

Limitations of serum ferritin to predict liver iron concentration responses to deferasirox therapy in patients with transfusion-dependent thalassaemia.

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.

Optimising iron chelation therapy with deferasirox for non-transfusion-dependent thalassaemia patients: 1-year results from the THETIS study.

Efficacy and safety of iron chelation therapy with deferasirox in iron-overloaded non-transfusion-dependent thalassaemia (NTDT) patients were established in the THALASSA study. THETIS, an open-label, single-arm, multicentre, Phase IV study, added to this evidence by investigating earlier dose escalation by baseline liver iron concentration (LIC) (week 4: escalation according to baseline LIC; week 24: adjustment according to LIC response, maximum 30mg/kg/day). The primary efficacy endpoint was absolute change in LIC from baseline to week 52. 134 iron-overloaded non-transfusion-dependent anaemia patients were enrolled and received deferasirox starting at 10mg/kg/day. Mean actual dose±SD over 1year was 14.70±5.48mg/kg/day. At week 52, mean LIC±SD decreased significantly from 15.13±10.72mg Fe/g dw at baseline to 8.46±6.25mg Fe/g dw (absolute change from baseline, -6.68±7.02mg Fe/g dw [95% CI: -7.91, -5.45]; P<0.0001). Most common drug-related adverse events were gastrointestinal: abdominal discomfort, diarrhoea and nausea (n=6 each). There was one death (pneumonia, not considered drug related). With significant and clinically relevant reductions in iron burden alongside a safety profile similar to that in THALASSA, these data support earlier escalation with higher deferasirox doses in iron-overloaded non-transfusion-dependent anaemia patients.

Sustained improvements in myocardial T2* over 2 years in severely iron-overloaded patients with beta thalassemia major treated with deferasirox or deferoxamine.

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).

Current approach to iron chelation in children.

Transfusion-dependent children, mostly with thalassaemia major, but also and occasionally to a more significant degree, with inherited bone marrow failures, can develop severe iron overload in early life. Moreover, chronic conditions associated with ineffective erythropoiesis, such as non-transfusion-dependent thalassaemia (NTDT), may lead to iron overload through increased gut absorption of iron starting in childhood. Currently, the goal of iron chelation has shifted from treating iron overload to preventing iron accumulation and iron-induced end-organ complications, in order to achieve a normal pattern of complication-free survival and of quality of life. New chelation options increase the likelihood of achieving these goals. Timely initiation, close monitoring and continuous adjustment are the cornerstones of optimal chelation therapy in children, who have a higher transfusional requirements compared to adults in order to reach haemoglobin levels adequate for normal growth and development. Despite increased knowledge, there are still uncertainties about the level of body iron at which iron chelation therapy should be started and about the appropriate degree of iron stores' depletion.

The effect of HFE polymorphisms on cardiac iron overload in patients with beta-thalassemia major.

OBJECTIVE: We aimed to investigate the effect of human hemochromatosis protein (HFE) polymorphisms on cardiac iron overload in patients with beta-thalassemia major. METHODS: Our study included 33 patients diagnosed with beta-thalassemia major who were treated with regular transfusions and chelation therapy. M-mode, tissue Doppler, and pulsed wave Doppler echocardiography were performed on all patients. T2* magnetic resonance imaging (MRI) scans were also performed. The HFE polymorphisms (H63D, C282Y, S65C, Q283P, E168Q, E168X, W169X, P160delC, Q127H, H63H, V59M, and V53M) were studied using polymerase chain reaction. RESULTS: The H63D polymorphism was detected in six patients with beta-thalassemia major. Five patients were heterozygous for the H63D polymorphism, while one was homozygous. There were no other polymorphisms. There was no relationship between the HFE polymorphisms and either the serum ferritin levels or the T2-weighted MRI values (P > .05). Moreover, conventional echo and tissue Doppler echo findings were not correlated with the HFE polymorphisms. Pulmonary vein atrial reversal flow velocity, which is a manifestation of diastolic dysfunction measured with pulse wave echo, was higher in the patients with HFE polymorphisms (P = .036). CONCLUSIONS: The HFE polymorphisms had no effect on cardiac iron overload. However, pulmonary vein atrial reversal flow velocity measurements can provide important information for detecting diastolic dysfunction during cardiac follow-up of patients with HFE polymorphisms. Studies with more patients are needed to provide more information regarding this matter.

Deferasirox for up to 3 years leads to continued improvement of myocardial T2* in patients with ß-thalassemia major.

BACKGROUND: Prospective data on cardiac iron removal are limited beyond one year and longer-term studies are, therefore, important. DESIGN AND METHODS: Seventy-one patients in the EPIC cardiac substudy elected to continue into the 3(rd) year, allowing cardiac iron removal to be analyzed over three years. RESULTS: Mean deferasirox dose during year 3 was 33.6 ± 9.8 mg/kg per day. Myocardial T2*, assessed by cardiovascular magnetic resonance, significantly increased from 12.0 ms ± 39.1% at baseline to 17.1 ms ± 62.0% at end of study (P<0.001), corresponding to a decrease in cardiac iron concentration (based on ad hoc analysis of T2*) from 2.43 ± 1.2 mg Fe/g dry weight (dw) at baseline to 1.80 ± 1.4 mg Fe/g dw at end of study (P<0.001). After three years, 68.1% of patients with baseline T2* 10 to <20 ms normalized (≥ 20 ms) and 50.0% of patients with baseline T2* >5 to <10 ms improved to 10 to <20 ms. There was no significant variation in left ventricular ejection fraction over the three years. No deaths occurred and the most common investigator-assessed drug-related adverse event in year 3 was increased serum creatinine (n = 9, 12.7%). CONCLUSIONS: Three years of deferasirox treatment along with a clinically manageable safety profile significantly reduced cardiac iron overload versus baseline and normalized T2* in 68.1% (32 of 47) of patients with T2* 10 to <20 ms.

Timed non-transferrin bound iron determinations probe the origin of chelatable iron pools during deferiprone regimens and predict chelation response.

BACKGROUND: Plasma non-transferrin bound iron refers to heterogeneous plasma iron species, not bound to transferrin, which appear in conditions of iron overload and ineffective erythropoiesis. The clinical utility of non-transferrin bound iron in predicting complications from iron overload, or response to chelation therapy remains unproven. We undertook carefully timed measurements of non-transferrin bound iron to explore the origin of chelatable iron and to predict clinical response to deferiprone. DESIGN AND METHODS: Non-transferrin bound iron levels were determined at baseline and after 1 week of chelation in 32 patients with thalassemia major receiving deferiprone alone, desferrioxamine alone, or a combination of the two chelators. Samples were taken at baseline, following a 2-week washout without chelation, and after 1 week of chelation, this last sample being taken 10 hours after the previous evening dose of deferiprone and, in those receiving desferrioxamine, 24 hours after cessation of the overnight subcutaneous infusion. Absolute or relative non-transferrin bound iron levels were related to transfusional iron loading rates, liver iron concentration, 24-hour urine iron and response to chelation therapy over the subsequent year. RESULTS: Changes in non-transferrin bound iron at week 1 were correlated positively with baseline liver iron, and inversely with transfusional iron loading rates, with deferiprone-containing regimens but not with desferrioxamine monotherapy. Changes in week 1 non-transferrin bound iron were also directly proportional to the plasma concentration of deferiprone-iron complexes and correlated significantly with urine iron excretion and with changes in liver iron concentration over the next 12 months. CONCLUSIONS: The widely used assay chosen for this study detects both endogenous non-transferrin bound iron and the iron complexes of deferiprone. The week 1 increments reflect chelatable iron derived both from liver stores and from red cell catabolism. These increments correlate with urinary iron excretion and the change in liver iron concentration over the subsequent year thus predicting response to deferiprone-containing chelation regimes. This clinical study was registered at clinical.trials.gov with the number NCT00350662.

Iron chelation with deferasirox in adult and pediatric patients with thalassemia major: efficacy and safety during 5 years' follow-up.

Patients with ß-thalassemia require lifelong iron chelation therapy from early childhood to prevent complications associated with transfusional iron overload. To evaluate long-term efficacy and safety of once-daily oral iron chelation with deferasirox, patients aged ≥ 2 years who completed a 1-year, phase 3, randomized trial entered a 4-year extension study, either continuing on deferasirox (deferasirox cohort) or switching from deferoxamine to deferasirox (crossover cohort). Of 555 patients who received ≥ 1 deferasirox dose, 66.8% completed the study; 43 patients (7.7%) discontinued because of adverse events. In patients with ≥ 4 years' deferasirox exposure who had liver biopsy, mean liver iron concentration significantly decreased by 7.8 ± 11.2 mg Fe/g dry weight (dw; n = 103; P < .001) and 3.1 ± 7.9 mg Fe/g dw (n = 68; P < .001) in the deferasirox and crossover cohorts, respectively. Median serum ferritin significantly decreased by 706 ng/mL (n = 196; P < .001) and 371 ng/mL (n = 147; P < .001), respectively, after ≥ 4 years' exposure. Investigator-assessed, drug-related adverse events, including increased blood creatinine (11.2%), abdominal pain (9.0%), and nausea (7.4%), were generally mild to moderate, transient, and reduced in frequency over time. No adverse effect was observed on pediatric growth or adolescent sexual development. This first prospective study of long-term deferasirox use in pediatric and adult patients with ß-thalassemia suggests treatment for ≤ 5 years is generally well tolerated and effectively reduces iron burden. This trial was registered at www.clinicaltrials.gov as #NCT00171210.

A randomized controlled 1-year study of daily deferiprone plus twice weekly desferrioxamine compared with daily deferiprone monotherapy in patients with thalassemia major.

BACKGROUND AND OBJECTIVES: The aim of this prospective, randomized, 1-year study was to compare the efficacy and safety of oral deferiprone (DFP) with those of combinations of parenteral desferrioxamine (DFO) with oral DFP. DESIGN AND METHODS: A total of 24 patients with thalassemia major were randomized to receive one of the following two treatments; DFP given at a daily dose of 75 mg/kg in combination with DFO (40-50 mg/kg twice weekly) (n=12) or as single agent (n=12). In addition, 12 patients treated with 40-50 mg/kg DFO 5 days weekly were included as a reference group without randomization. Changes in liver iron concentration (LIC) and serum ferritin (SF) were assessed; total iron excretion (TIE), urinary iron excretion (UIE) and iron balance were calculated. Cardiac function and toxicity were also examined. DESIGN AND METHODS: SF and LIC were significantly reduced after 1 year of combination therapy (p=0.01 and 0.07, respectively). A decrease of LIC was observed in all but one patient (87.5%) following the combination therapy but in only 42% of patients treated with DFP monotherapy. In the DFO reference group, a statistically significant decrease in LIC (p=0.01) associated with a substantial decrease in SF (p=0.08) was observed after 1 year. The combination regimen resulted in greater TIE compared to DFP monotherapy (p=0.08) and was the regimen associated with the highest iron balance compared to DFP monotherapy (p=0.04) or standard DFO treatment (p=0.006). INTERPRETATIONS AND CONCLUSIONS: The addition of subcutaneous DFO twice weekly to oral DFP 75 mg/kg is a highly efficacious and safe chelation therapy providing superior chelation activity to that of DFP and likely has an efficacy profile comparable to that of standard DFO.

Effects of iron(II) salts and iron(III) complexes on trace element status in children with iron-deficiency anemia.

Iron-deficiency anemia (IDA) is the most common nutritional deficiency in childhood throughout the world. Although it has been shown that IRA is associated with elevated plasma copper and depleted zinc levels in children, there are conflicting results on the effect of iron supplementation on the absorption of these elements. The aim of this study was to investigate the effects of ferrous and ferric iron supplementation on the trace element status in children (n=25, aged 8-168 mo) with IDA. Fourteen of them were treated with ferric hydroxide-polymaltose complex (Ferrum, Vifor, Switzerland) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance); the others were treated with a ferrous sulfate complex (FerroSanol, Schwarz, Germany) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance). Plasma copper, zinc, and ceruloplasmin levels as well as hematological parameters were determined at baseline and the first, third, and sixth month of the treatment period. The hemoglobin and iron levels of patients in both groups were higher in the first and sixth months compared to baseline. Although the ceruloplasmin levels were depleted (48.9 mg/dL vs 41.4 mg/dL, p=0.035) during ferrous iron treatment, the copper and zinc levels remained unchanged. On the other hand, ferric iron supplementation led to an increase in zinc levels in the sixth month of treatment (0.77 mg/L vs 1.0 mg/L, p=0.021). The plasma copper levels were lower in the ferrous iron-treated group at the end of the first month of treatment than in the ferric irontreated group (1.06 mg/L vs 1.29 mg/L, p=0.008). In conclusion, our data showed that copper and ceruloplasmin metabolisms were affected by ferrous iron supplementation, whereas ferric iron kept them to normal levels of zinc, possibly by affecting their absorption. We conclude that the copper and zinc status of patients with IDA should be taken into consideration before and after iron therapy.