Interim Phase 3 data from bluebird bio’s lentiglobin gene therapy trial presented at the 60th Annual Meeting of the American Society of Hematology provides hope for patients with transfusion-dependent beta-thalassemia.
Transfusion-dependent beta-thalassemia (TDT) is an inherited blood disorder caused by a mutation in the beta-globin chain resulting in ineffective red blood cell production. Anemia caused by TDT is corrected by blood transfusions, however, iron overload caused by regular blood transfusions is a serious problem.
bluebird bio’s lentiglobin gene therapy uses autologous CD34+ cells transduced ex vivo with a lentiviral β-A(T87Q)-globin vector. Following transplantation of these stem cells, patients are monitored for the production of gene therapy-derived hemoglobin (Hb) which increases Hb levels. It is currently in three clinical studies for the treatment of TDT (Northstar 1 and Northstar 2 study) and severe sickle cell disease.
Interim results from the Northstar-2 study revealed positive outcome in eleven of the sixteen transplanted TDT patients three months after the treatment. Transplanting these stem cells resulted in the production of gene therapy-derived Hb and normal Hb levels in patients, thus reducing or eliminating the need for transfusions.
Similar results were seen in the three patients of Northstar-3 study. The safety profile of both the treatments remained consistent with myeloablative busulfan conditioning. One serious adverse event of grade 3 thrombocytopenia was reported and considered possibly related to lentiglobin. The studies are expected to complete in 2020 and 2021 respectively.
Source: bluebird bio Presents New Data for LentiGlobin Gene Therapy in Transfusion Dependent β-Thalassemia at 60th Annual Meeting of the American Society of Hematology; Press Release