The Effect of Obecabtagene Autoleucel on Adult Patients With Relapsed/Refractory B-Cell Acute Lymphoblastic Leukemia and Extramedullary Disease

In this OncLive Rapid Readout, Jae Park, MD, reviews findings from the FELIX study evaluating obecabtagene autoleucel, or obe-cel, in adult patients with relapsed/refractory B-cell acute lymphoblastic leukemia and extramedullary disease at lymphodepletion. Park explains that obe-cel, an autologous CD19-directed CAR T-cell therapy with a fast off-rate binding domain, demonstrated favorable efficacy and safety regardless of extramedullary disease status. In the analysis, patients with EMD had more heavily pretreated disease and higher marrow burden, yet treatment with obe-cel was associated with clinically meaningful remission, duration of remission, event-free survival, and overall survival outcomes. Results appeared especially encouraging among patients with EMD and less than 5% bone marrow blasts at lymphodepletion, in whom median duration of remission, event-free survival, and overall survival were not reached. Park also discusses low severe CRS and ICANS rates in lower marrow-burden patients and pharmacokinetic evidence suggesting obe-cel can cross the blood-brain barrier.