Restoring Iron Homeostasis in Pts Who Achieved Transfusion Independence after Treatment with Betibeglogene Autotemcel Gene Therapy: Results from up to 7 Years of Follow-up

Introduction: Transfusion-dependent β-thalassemia (TDT) is a severe genetic disease requiring lifelong, regular packed red blood cell (pRBC) transfusions and iron chelation treatment. Betibeglogene autotemcel (beti-cel) is a one-time ex vivo gene therapy that addresses the underlying cause of TDT to potentially enable lifelong, stable production of modified adult hemoglobin (Hb) sufficient to achieve transfusion independence (TI). Patients (pts) with TDT (N=63) were treated with beti-cel in 2 completed phase 1/2 studies (HGB-204, HGB-205) and 2 ongoing phase 3 studies (HGB-207, HGB-212). After 2 y of follow-up, pts could enroll in a long-term follow-up study (LTF-303 [NCT02633943]) for up to an additional 13 y. We report results from LTF-303 in pts with up to 7 y of follow-up.