Late failure of aggressive B-cell lymphoma after CAR T-cell therapy: a LYSA study from the DESCAR-T registry.

abstractLarge B-cell lymphoma (LBCL) patients failing anti-CD19 chimeric antigen receptor (CAR) T-cell therapy exhibit poor prognosis. Most progressions/relapses occur within 3 months from infusion whereas only a few events occur thereafter (late failure, [LF]). We analyze features, treatments, and outcomes of patients with LF from DESCAR-T, a nationwide registry collecting real-life data for patients treated with approved CAR T-cell therapy in France. Between July 2018 and March 2024, 298 (39.9%) LBCL LF patients (median age, 62 years [range, 18-79]; male, 61.7%) were collected from DESCAR-T. Most patients had diffuse LBCL (n = 205 [68.8%]), advanced stage disease (84.6%), and age-adjusted International Prognostic Index of 2 to 3 (59.3%) at CAR T-cell eligibility. After failure, 76.5% of patients received a systemic therapy and overall response rate was 22.6% (complete response, 18%). At a median follow-up since first LF event of 13.8 months (95% confidence interval [CI], 12.1-15.4), the median overall survival and progression-free survival 2 (PFS-2) were 4.4 (95% CI, 3.8-5.8) and 13.2 (95% CI, 9.6-18) months, respectively. Compared with chemotherapy (hazard ratio [HR], 0.350; 95% CI, 0.193-0.633) and with pooled other treatment groups (HR, 0.483; 95% CI, 0.290-0.805), salvage treatment with bispecific antibodies (bsAb) after CAR T-cell failure showed better PFS-2. Radiotherapy obtained prolonged responses in some patients with 12-month PFS-2 of 41.5% (95% CI, 22.5-59.5). This work is, to our knowledge, the first study describing LBCL patients with LF after CAR T-cells. bsAb seem to be more effective compared with other strategies in the LF setting and this should be considered in the design of new clinical trials.