CD19 Directed CAR T Therapy for Transformed Follicular Lymphoma: A CIBMTR Analysis

Area of Science:

• Hematology
• Oncology
• Immunotherapy

Background:

• Transformed follicular lymphoma (tFL) presents challenges due to chemotherapy resistance and poor prognosis.
• Limited data exist on the efficacy of CD19-directed chimeric antigen receptor T-cell (CAR T) therapy in relapsed/refractory (R/R) tFL.
• Understanding CAR T outcomes is crucial for optimizing treatment strategies in R/R tFL.

Purpose of the Study:

• To evaluate the outcomes of CD19-directed CAR T therapy in a large cohort of adult patients with R/R tFL.
• To assess the overall survival (OS), progression-free survival (PFS), and safety profile of CAR T therapy in this patient population.
• To identify factors associated with inferior outcomes in R/R tFL patients treated with CAR T therapy.

Main Methods:

• Retrospective analysis of 923 adult patients with R/R tFL who received commercial CD19 CAR T therapy from 2017-2023.
• Data were sourced from the Center for International Blood and Marrow Transplant Research registry.
• Outcomes including OS, PFS, relapse/progression (rel/prog), non-relapse mortality (NRM), response rates, and adverse events (CRS, ICANS) were analyzed.

Main Results:

• The 2-year OS was 57% and PFS was 43%.
• Overall response rate (ORR) was 76%, with a 63% complete response (CR) rate.
• Grade ≥3 cytokine release syndrome (CRS) occurred in 7.1% and immune effector cell-associated neurotoxicity syndrome (ICANS) in 21.6% of patients.

Conclusions:

• CD19 CAR T therapy demonstrates significant efficacy and a manageable safety profile in patients with R/R tFL.
• Resistant disease at infusion, bridging therapy, and high comorbidity index were linked to poorer PFS and OS.
• Older age (≥60) was associated with increased NRM, highlighting the need for careful patient selection and monitoring.