Lee Lee Chan

Tailoring iron chelation by iron intake and serum ferritin: the prospective EPIC study of deferasirox in 1744 patients with transfusion-dependent anemias

Background Following a clinical evaluation of deferasirox (Exjade®) it was concluded that, in addition to baseline body iron burden, ongoing transfusional iron intake should be considered when selecting doses. The 1-year EPIC study, the largest ever investigation conducted for an iron chelator, is the first to evaluate whether fixed starting doses of deferasirox, based on transfusional iron intake, with dose titration guided by serum ferritin trends and safety markers, provides clinically acceptable chelation in patients (aged ≥2 years) with transfusional hemosiderosis from various types of anemia. Design and Methods The recommended initial dose was 20 mg/kg/day for patients receiving 2–4 packed red blood cell units/month and 10 or 30 mg/kg/day was recommended for patients receiving less or more frequent transfusions, respectively. Dose adjustments were based on 3-month serum ferritin trends and continuous assessment of safety markers. The primary efficacy end-point was change in serum ferritin after 52 weeks compared with baseline. Results The 1744 patients enrolled had the following conditions; thalassemia (n=1115), myelodysplastic syndromes (n=341), aplastic anemia (n=116), sickle cell disease (n=80), rare anemias (n=43) and other transfused anemias (n=49). Overall, there was a significant reduction in serum ferritin from baseline (−264 ng/mL; P<0.0001), reflecting dosage adjustments and ongoing iron intake. The most common (>5%) adverse events were gastrointestinal disturbances (28%) and skin rash (10%). Conclusions Analysis of this large, prospectively collected data set confirms the response to chelation therapy across various anemias, supporting initial deferasirox doses based on transfusional iron intake, with subsequent dose titration guided by trends in serum ferritin and safety markers (clinicaltrials.gov identifier: NCT00171821).

Efficacy of deferasirox in reducing and preventing cardiac iron overload in β-thalassemia

Cardiac iron overload causes most deaths in beta-thalassemia major. The efficacy of deferasirox in reducing or preventing cardiac iron overload was assessed in 192 patients with beta-thalassemia in a 1-year prospective, multicenter study. The cardiac iron reduction arm (n = 114) included patients with magnetic resonance myocardial T2* from 5 to 20 ms (indicating cardiac siderosis), left ventricular ejection fraction (LVEF) of 56% or more, serum ferritin more than 2500 ng/mL, liver iron concentration more than 10 mg Fe/g dry weight, and more than 50 transfused blood units. The prevention arm (n = 78) included otherwise eligible patients whose myocardial T2* was 20 ms or more. The primary end point was the change in myocardial T2* at 1 year. In the cardiac iron reduction arm, the mean deferasirox dose was 32.6 mg/kg per day. Myocardial T2* (geometric mean +/- coefficient of variation) improved from a baseline of 11.2 ms (+/- 40.5%) to 12.9 ms (+/- 49.5%) (+16%; P < .001). LVEF (mean +/- SD) was unchanged: 67.4 (+/- 5.7%) to 67.0 (+/- 6.0%) (-0.3%; P = .53). In the prevention arm, baseline myocardial T2* was unchanged from baseline of 32.0 ms (+/- 25.6%) to 32.5 ms (+/- 25.1%) (+2%; P = .57) and LVEF increased from baseline 67.7 (+/- 4.7%) to 69.6 (+/- 4.5%) (+1.8%; P < .001). This prospective study shows that deferasirox is effective in removing and preventing myocardial iron accumulation. This study is registered at http://clinicaltrials.gov as NCT00171821.

Deferasirox for up to 3 years leads to continued improvement of myocardial T2* in patients with β-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 3rd 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.

Continued improvement in myocardial T2* over two years of deferasirox therapy in β-thalassemia major patients with cardiac iron overload

Background The efficacy of cardiac iron chelation in transfusion-dependent patients has been demonstrated in one-year prospective trials. Since normalization of cardiac T2* takes several years, the efficacy and safety of deferasirox was assessed for two years in patients with β-thalassemia major in the cardiac sub-study of the EPIC trial. Design and Methods Eligible patients with myocardial T2* greater than 5 to less than 20 ms received deferasirox, with the primary endpoint being the change in T2* from baseline to two years. Results Baseline myocardial T2* was severe (>5 to <10 ms) in 39 patients, and moderate-to-mild (10 to <20 ms) in 62 patients. Mean deferasirox dose was 33.1±3.7 mg/kg/d in the one-year core study increasing to 36.1±7.7 mg/kg/d during the second year of treatment. Geometric mean myocardial T2* increased from a baseline of 11.2 to 14.8 ms at two years (P<0.001). In patients with moderate-to-mild baseline T2*, an increase was seen from 14.7 to 20.1 ms, with normalization (≥20 ms) in 56.7% of patients. In those with severe cardiac iron overload at baseline, 42.9% improved to the moderate-to-mild group. The incidence of drug-related adverse events did not increase during the extension relative to the core study and included (≥5%) increased serum creatinine, rash and increased alanine aminotransferase. Conclusions Continuous treatment with deferasirox for two years with a target dose of 40 mg/kg/d continued to remove iron from the heart in patients with β-thalassemia major and mild, moderate and severe cardiac siderosis. (Clinicaltrials.gov identifier: NCT 00171821)

International survey of T2* cardiovascular magnetic resonance in β-thalassemia major

Accumulation of myocardial iron is the cause of heart failure and early death in most transfused thalassemia major patients. T2* cardiovascular magnetic resonance provides calibrated, reproducible measurements of myocardial iron. However, there are few data regarding myocardial iron loading and its relation to outcome across the world. A survey is reported of 3,095 patients in 27 worldwide centers using T2* cardiovascular magnetic resonance. Data on baseline T2* and numbers of patients with symptoms of heart failure at first scan (defined as symptoms and signs of heart failure with objective evidence of left ventricular dysfunction) were requested together with more detailed information about patients who subsequently developed heart failure or died. At first scan, 20.6% had severe myocardial iron (T2*≤10ms), 22.8% had moderate myocardial iron (T2* 10–20ms) and 56.6% of patients had no iron loading (T2*>20ms). There was significant geographical variation in myocardial iron loading (24.8–52.6%; P<0.001). At first scan, 85 (2.9%) of 2,915 patients were reported to have heart failure (81.2% had T2* <10ms; 98.8% had T2* <20ms). During follow up, 108 (3.8%) of 2,830 patients developed new heart failure. Of these, T2* at first scan had been less than 10ms in 96.3% and less than 20ms in 100%. There were 35 (1.1%) cardiac deaths. Of these patients, myocardial T2* at first scan had been less than 10ms in 85.7% and less than 20ms in 97.1%. Therefore, in this worldwide cohort of thalassemia major patients, over 43% had moderate/severe myocardial iron loading with significant geographical differences, and myocardial T2* values less than 10ms were strongly associated with heart failure and death.

Utility of labile plasma iron and transferrin saturation in addition to serum ferritin as iron overload markers in different underlying anemias before and after deferasirox treatment.

Plasma markers in addition to serum ferritin (SF) may be useful for the assessment of iron overload; however, predictive utility may differ depending on underlying, transfusion‐dependent, anemias.

Clinical efficacy and safety evaluation of tailoring iron chelation practice in thalassaemia patients from Asia-Pacific: a subanalysis of the EPIC study of deferasirox

Although thalassaemia is highly prevalent in the Asia-Pacific region, clinical data on efficacy and safety profiles of deferasirox in patients from this region are rather limited. Recently, data from the multicentre Evaluation of Patients’ Iron Chelation with Exjade (EPIC) study in 1744 patients with different anaemias has provided an opportunity to analyse 1115 thalassaemia patients, of whom 444 patients were from five countries in the Asia-Pacific region (AP) for whom thalassaemia management and choice of iron chelators were similar. Compared to the rest of the world (ROW), baseline clinical data showed that the AP group appeared to be more loaded with iron (3745.0 vs. 2822.0 ng/ml) and had a higher proportion on deferoxamine monotherapy prior to the study (82.9 vs. 58.9%). Using a starting deferasirox dose based on transfusional iron intake and tailoring it to individual patient response, clinical efficacy based on serum ferritin reduction in AP and ROW thalassaemia patients was similar. Interestingly, the AP group developed a higher incidence of drug-related skin rash compared to ROW (18.0 vs. 7.2%), which may indicate different pharmacogenetic backgrounds in the two populations. Our analysis confirms that, with appropriate adjustment of dose, deferasirox can be clinically effective across different regions, with manageable side effects.