Obecabtagene Autoleucel Approved for Advanced Leukemia

The cell-based immunotherapy was approved for adults with relapsed or refractory acute lymphoblastic leukemia. 

The U.S. Food and Drug Administration (FDA) has approved obecabtagene autoleucel (Aucatzyl) for the treatment of adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL). 

Obecabtagene autoleucel is a chimeric antigen receptor (CAR) T-cell therapy, a type of immunotherapy made from patients’ own immune cells. The immune cells are extracted from the patient’s blood and engineered to target the CD19 protein that is often abundant on cancerous B cells, including in ALL, before being infused back into the patient.  

CAR T cells harness the power of patients’ own immune cells.

This approval, the first for obecabtagene autoleucel, was based on results from FELIX, an open-label, multicenter phase I/II trial with a single arm. Adults were eligible if they experienced a relapse within 12 months of achieving remission, had relapsed or refractory ALL after undergoing at least two prior lines of systemic therapy, or if their disease persisted or recurred at least three months after undergoing an allogeneic stem cell transplant. 

Of 65 patients evaluated, 27 (42%) experienced a complete response within three months, with a median duration of complete response of 14.1 months. 

The prescribing information has a boxed warning for cytokine release syndrome (a potentially serious or fatal reaction of the immune system), neurological toxicities, and T-cell malignancies. 

The recommended total dose of obecabtagene autoleucel is 410 million viable CD19-targeted CAR T cells split between two administrations 10 days apart (plus or minus two days). The dose for each administration is based on the tumor burden, as determined by bone marrow blast assessment. Administration of obecabtagene autoleucel is preceded by lymphodepleting chemotherapy with fludarabine and cyclophosphamide. 

ALL is a type of blood cancer most commonly diagnosed among children and young adults under the age of 20. According to federal statistics, it was estimated that 6,550 individuals would be diagnosed with ALL and 1,330 patients would die of the disease in the United States in 2024.  


The FDA rendered its decision on November 8, 2024. Check this resource for updated information on all therapeutics regulated by the FDA.