Bluebird Bio Inc., a leading gene therapy biotech company based in Cambridge, Massachusetts, announced on February 2 that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy designation to one of its investigational drugs, LentiGlobin® BB305 for the treatment of transfusion-dependent patients with beta-thalassemia major.
Beta-thalassemia is a rare genetic disease affecting 40,000 newborn children annually worldwide. It is caused by mutations in the beta-globin gene (HBB). HBB encodes beta chains of hemoglobin and mutation of this gene causes different types of rare blood genetic diseases (Sickle Cell disease or beta thalassemia). Depending on the severity of symptoms, beta-thalassemia is clinically divided into two types: thalassemia major and thalassemia intermedia with thalassemia major being more severe. Presently, the existing treatment options for these patients have significant side effects and limitations.
LentiGlobin BB305 developed by Bluebird Bio utilizes an improved lentiviral vector to insert a correct copy of human beta-globin gene into the patient’s own hematopoietic stem cells ex vivo and then transplanting those modified cells into the patient through infusion into the bloodstream. LentiGlobin BB305 is currently undergoing three clinical trials globally aimed at treating both beta-thalassemia and sickle cell disease.