Profile of deferasirox for the treatment of patients with non-transfusion-dependent thalassemia syndromes

Pharmacogenomics of Drugs Used in β-Thalassemia and Sickle-Cell Disease: From Basic Research to Clinical Applications

In this short review we have presented and discussed studies on pharmacogenomics (also termed pharmacogenetics) of the drugs employed in the treatment of β-thalassemia or Sickle-cell disease (SCD). This field of investigation is relevant, since it is expected to help clinicians select the appropriate drug and the correct dosage for each patient. We first discussed the search for DNA polymorphisms associated with a high expression of γ-globin genes and identified this using GWAS studies and CRISPR-based gene editing approaches. We then presented validated DNA polymorphisms associated with a high HbF production (including, but not limited to the HBG2 XmnI polymorphism and those related to the BCL11A, MYB, KLF-1, and LYAR genes). The expression of microRNAs involved in the regulation of γ-globin genes was also presented in the context of pharmacomiRNomics. Then, the pharmacogenomics of validated fetal hemoglobin inducers (hydroxyurea, butyrate and butyrate analogues, thalidomide, and sirolimus), of iron chelators, and of analgesics in the pain management of SCD patients were considered. Finally, we discuss current clinical trials, as well as international research networks focusing on clinical issues related to pharmacogenomics in hematological diseases.

The effect of desferrioxamine chelation versus no therapy in patients with non transfusion-dependent thalassaemia: a multicenter prospective comparison from the MIOT network

We prospectively assessed by magnetic resonance imaging (MRI) the advantages of desferrioxamine (DFO) with respect to the absence of chelation therapy in non transfusion-dependent thalassaemia (NTDT) patients. We considered 18 patients non-chelated and 33 patients who received DFO alone between the two MRI scans. Iron overload was assessed by the T2* technique. Biventricular function parameters were quantified by cine sequences. No patient treated with DFO had cardiac iron. At baseline, only one non-chelated patient showed a pathological heart T2* value (< 20 ms) and he recovered at the follow-up. The percentage of patients who maintained a normal heart T2* value was 100% in both groups. A significant increase in the right ventricular ejection fraction was detected in DFO patients (3.48 ± 7.22%; P = 0.024). The changes in cardiac T2* values and in the biventricular function were comparable between the two groups. In patients with hepatic iron at baseline (MRI liver iron concentration (LIC) ≥ 3 mg/g/dw), the reduction in MRI LIC values was significant only in the DFO group (- 2.20 ± 4.84 mg/g/dw; P = 0.050). The decrease in MRI LIC was comparable between the groups. In conclusion, in NTDT patients, DFO therapy showed no advantage in terms of cardiac iron but its administration allowed an improvement in right ventricular function. Moreover, DFO reduced hepatic iron in patients with significant iron burden at baseline.