Effectiveness of anti-CD19 CAR T-cell therapy for high-grade B-cell lymphoma in Japan: a single-institution analysis.

BACKGROUND: While clinical data on anti-CD19 chimeric antigen receptor (CAR) T-cell therapy in relapsed/refractory (R/R) large B-cell lymphoma (LBCL) have been established, data specifically focusing on high-grade B-cell lymphoma (HGBCL) remain limited. METHODS: To evaluate the efficacy of CAR T-cell therapy for HGBCL, we conducted a single-center retrospective study of patients with R/R HGBCL who received CAR T-cell therapy at our institution between March 2022 and October 2024. RESULTS: This study included 15 patients with R/R HGBCL treated with CAR T-cell therapy (10 with axicabtagene ciloleucel and 5 with lisocabtagene maraleucel). The median age at CAR T-cell infusion was 62 years (range, 39-76 years). Eleven patients (73.3%) were refractory to first-line therapy and 11 (73.3%) had MYC and BCL2 rearrangements. High-grade morphology was observed in nine patients (60.0%). Nine patients (60.0%) received CAR T-cell therapy as second-line treatment. The best overall response rate was 80.0%, with a complete response rate of 66.7%. At a median follow-up of 18.5 months (range, 1.3-26.0 months), the 1-year progression-free survival (PFS) rate was 40.0%. In univariate analysis, high-grade morphology was associated with inferior PFS (HR 5.09; 95% CI 1.46-17.73, p = 0.019), whereas high lactate dehydrogenase level and high metabolic tumor volume at lymphodepletion, number of prior lines of chemotherapy and MYC and BCL2 rearrangements were not significantly associated with PFS. CONCLUSION: The efficacy of CAR T-cell therapy in patients with R/R HGBCL remains suboptimal. High-grade morphology may help identify patients at particularly high risk of poor outcomes following CAR T-cell therapy.