Testing SIROLIMUS in Beta-thalassemia Transfusion Dependent Patients

Beta-thalassemias are hereditary blood disorders caused by reduced or absent synthesis of hemoglobin beta chains, with variable outcomes ranging from severe anemia to clinically asymptomatic individuals. Treatment is symptomatic and thalassemia is a major unmet medical need. Survival is increased, even in patients needing transfusions, in comparison with a few years ago, but the quality of life is poor for many patients. In some patients, an anomalous expression of gamma-globin genes has been observed, with a consequent rise in Fetal Hemoglobin levels. The patients displaying a clinical phenotype known as Hereditary Persistence of Fetal Hemoglobin (HPFH) exhibit a positive clinical status. To mimick HPFH, several compounds able to induce expression of fetal hemoglobins (HbF) have been evaluated. Within this framework, sirolimus is particularly interesting as an inducer of HbF. It has been used for many years for different indications and the available preclinical evidence warrant the start of a clinical development plan in thalassemia. The investigators propose a clinical trial in beta-thalassemia patients, designed to evaluate the effect of sirolimus on several parameters related to red blood cell status and to the level of HbF in particular, as a first step for the full clinical development in this new indication.