Key Determinants of Phenotypic Heterogeneity of Hb E/β Thalassemia: A Comparative Study from Eastern India

HbE Beta thalassemia is phenotypically very diverse disease. We aim to study role of various genetic factors in determining severity of this disease. 243 diagnosed cases of HbE Beta thalassemia were included in this study. Patients were divided in two arms-transfusion dependent and non-transfusion dependent arms. Various factors (percentage of haemoglobin F, hemoglobin E, type of Beta mutation, Xmn1 polymorphism, alpha deletion, HPFH mutation) were evaluated in these patients. Xmn1 polymorphism (homozygous and heterozygous), presence of HPFH mutation and alpha deletion were more prevalent in NTDT arm versus TDT arm (p value < 0.001). Higher prevelance of severe beta mutation IVS 1-5 (G → C) mutation {64(61.54%) vs 38(27.34); p value < 0.001} was found in TDT arm when above factors were excluded from analysis. Higher mean haemoglobin F and mean Hemoglobin E percentage was associated with NTDT arm (p value < 0.001). Various factors (hemoglobin F and E percentage, Xmn1 polymorphism, HPFH mutation, alpha deletion and IVS 1-5 Beta mutation) were identified to affect severity of this cohort.

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.