‘Bluebird Bio Inc. Presents Updated Data on Gene Therapy Program for Beta-Thalassemia at ASH Annual Meeting\n\nBluebird Bio Inc. (NASDAQ:BLUE) recently presented updated data from their gene therapy program in transfusion-dependent beta-thalassemia at the 65th American Society of Hematology (ASH) Annual Meeting & Exposition on December 10, 2023. The data showed sustained treatment effect, reduced iron management burden, and improved quality of life measures in patients with beta-thalassemia who require regular red blood cell transfusions following treatment with betibeglogene autotemcel (beti-cel), which is FDA approved and marketed in the U.S. As ZYNTEGLO™.\n\nAccording to the updated follow-up data, beti-cel has shown durable transfusion independence and a continued positive safety profile in patients with beta-thalassemia through up to nine years of follow-up. This makes it the longest follow-up with a gene therapy for patients with beta-thalassemia requiring regular transfusions. The data also suggests that beti-cel is a potentially curative therapy for patients of all ages and genotypes, with the achievement of durable transfusion independence and normal or near-normal hemoglobin levels.\n\nAs of January 30, 2023, 63 patients had received beti-cel across four clinical studies with a median follow-up of 5 years. These include two Phase 3 studies that led to the FDA approval of ZYNTEGLO in August 2022 as the first and only gene therapy for patients with beta-thalassemia who require regular red blood cell transfusions.\n\nThe data also showed sustained efficacy and safety results, as well as improved quality of life measures in adult and pediatric patients with transfusion-dependent beta-thalassemia up to 9 years post-treatment with beti-cel. Among patients in the Phase 3 studies, 90.2% achieved transfusion independence, which was maintained through last follow-up across ages and genotypes. In the Phase 12 studies, 68.2% of patients achieved transfusion independence, with 14 patients sustaining it through the last follow-up.\n\nIn addition, health-related quality of life (HRQOL) assessments were conducted at baseline and every 6 months in 12 adult patients and 22 pediatric patients in the Phase 12 and Phase 3 studies. The results showed clinically meaningful improvements in quality of life assessments for mental, physical, and psychosocial health in both adult and pediatric patients up to 36 months.\n\nThe safety results following beti-cel treatment largely reflected the known side effects of hematopoietic stem cell collection and the busulfan conditioning regimen. 19% of patients experienced beti-cel-related adverse events, with the most common being abdominal pain and thrombocytopenia. Five patients experienced serious veno-occlusive liver disease, but all of them received treatment and recovered. No malignancies, insertional oncogenesis, or vector-derived replication-competent lentivirus were reported.\n\nAdditionally, iron management outcomes were presented in patients with transfusion-dependent beta-thalassemia treated with beti-cel in the Phase 12 and Phase 3 studies. The data showed improvement in iron burden in these patients up to 9 years of follow-up.\n\n’