Durability and Tolerability of Obecabtagene Autoleucel CAR-T Therapy for R/R B-Cell Acute Lymphoblastic Leukemia
Treatment with obecabtagene autoleucel demonstrated durability and tolerability among patients with relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (ALL), according to study results published in The New England Journal of Medicine.
The anti-CD19 CAR-T cell therapy, obecabtagene autoleucel, has been shown to improve treatment persistence and reduce toxic effects among patients with R/R ALL. Researchers sought to evaluate the safety and tolerability, as well as the durability, of obecabtagene autoleucel in a phase 1b-2 study. The 127 included patients were stratified by disease status, with 94 morphologic disease and 33 residual disease.
The primary end point was overall remission, complete remission, or complete remission with incomplete hematologic recovery for patients with morphologic disease. Secondary end points were event-free survival, overall survival (OS), and safety of obecabtagene autoleucel.
Among patients with morphologic disease, the median follow-up from obecabtagene autoleucel infusion was 20.3 months. Overall remission was reported among 77% of patients (95% confidence interval [CI], 67 to 85) and complete remission among 55% (95% CI, 45 to 66). Complete remission with incomplete hematologic recovery among patients with morphologic disease was reported in 21% of patients (95% CI, 14 to 31).
Overall, the median follow-up after obecabtagene autoleucel infusion was 21.5 months and the median event-free survival was 11.9 months (95% CI, 8.0 to 22.1). Event free survival was estimated to be 65.4% at 6 months and 49.5% at 12 months. Additionally, the median overall survival was 15.6 months. The estimated overall survival at 6 months was 80.3% and 61.1% at 12 months.
In terms of safety, cytokine release syndrome grade 3 or higher was experienced by 2.4% of patients and 7.1% of patients developed immune effector cell-associated neurotoxicity syndrome grade 3 or higher.
The researchers concluded, “Obe-cel (obecabtagene autoleucel) resulted in a high incidence of durable response among adults with relapsed or refractory B-cell ALL, with a low incidence of grade 3 or higher immune-related toxic effects.”
Source:
Roddie C, Sandhu KS, Tholouli E, et al. Obecabtagene Autoleucel in Adults with B-Cell Acute Lymphoblastic Leukemia. New England Journal of Medicine. Published online November 27, 2024. doi: 10.1056/nejmoa2406526
