Follicular lymphoma (FL) is an indolent B-cell non-Hodgkin lymphoma characterized by frequent relapses despite initial responsiveness to chemoimmunotherapy. CD19-directed chimeric antigen receptor (CAR) T-cell therapy has shown promising efficacy in relapsed or refractory disease, though safety concerns such as cytokine release syndrome (CRS) and neurological events remain. This study aimed to evaluate the efficacy and safety of CD19 CAR T-cell therapy in relapsed or refractory FL.

A comprehensive search using six databases, including PubMed, Scopus, and Embase, was performed to identify relevant studies. Data on overall response rate (ORR), complete response rate (CRR), progression-free survival (PFS), duration of response (DOR), overall survival (OS), and adverse events, including CRS and neurological events, were extracted. Pooled estimates were calculated using the quality effects model. This review was registered in PROSPERO (CRD420251133655).

Out of 2303 records initially identified, 6 studies met the inclusion criteria. The pooled efficacy analysis demonstrated an ORR of 93.5% (95% CI: 86.3–98.3%) and a CRR of 84.5% (95% CI: 72.6–93.6%). Regarding safety outcomes, the pooled estimate for CRS of any grade was 61.4% (95% CI: 45.0–76.6%). For neurological events, it was 33.6% (95% CI: 13.4–57.1%). Subgroup analyses identified prior therapy lines and CAR construct design as sources of heterogeneity.

In conclusion, CD19 CAR T-cell therapy demonstrates high efficacy with a generally acceptable safety in relapsed or refractory FL, supporting its consideration for patients with limited treatment options while highlighting the need for further research on long-term outcomes.