Obecabtagene autoleucel (obe-cel, AUCATZYL®) is a treatment for adult patients aged 26 years and older with relapsed or refractory B-cell precursor acute lymphoblastic leukaemia (r/r B-ALL). Through autologous CAR-T cell therapy, in which patients' own T-cells are genetically modified with an anti-CD19 CAR, the goal is to specifically recognise and attack CD19-positive leukaemia cells. The European Commission granted conditional approval for obe-cel in July 2025.

The efficacy and safety of obe-cel were investigated in the multicentre, single-arm, open-label phase 1b/2 FELIX trial. The efficacy analysis of cohort 2A (n=94) showed an overall response rate of 77%, including 55% with complete remission, a median duration of response of 14.1 months, and an event-free survival of 9.0 months. For all infused patients (n=127), the median overall survival was 15.6 months. Regarding safety, all patients experienced adverse events, with the most frequent severe adverse events (grade ≥3) being febrile neutropenia (12.6%), immune effector cell-associated neurotoxicity syndrome (6.3%), and sepsis (5.5%). Cytokine release syndrome occurred in 68.5% of patients. After obe-cel infusion, 35% of patients died, with two deaths (1.6%) being treatment-related. Obe-cel represents an additional option for patients with r/r B-ALL; however, no studies directly compared it with other therapies. Quality-of-life data were also lacking. Treatment with obe-cel is associated with high costs and structural challenges (production of cell therapy and equipment for specialised CAR-T cell therapy centres).