Extended Data Fig. 2: CD19 CAR-T cell expansion in Adult B-ALL and B-cell lymphoma patients with initial high or low tumor burden.
(a) The impact of high tumor burden on CAR-T expansion in a cohort of relapsed/refractory ALL patients (n = 29) treated with 4-1BB CAR-T19 (CTL019; NCT02030847). High tumor burden was defined as bone marrow involvement before CART19 higher than 5%. The majority of patients (23/29, 79.3%) had a high disease burden before treatment. High tumor burden correlated with higher peak of expansion (CAR19 copies/μg of DNA: high tumor burden: 77,109 vs. low tumor burden: 25,064; p = 0.0641;). P-values are calculated with a two-sided unpaired student’s t-test. (b) The impact of high tumor burden on CAR-T expansion in a cohort of relapsed/refractory B-NHL patients treated with 4-1BB CAR-T19 CTL019 within a clinical trial (n = 37; NCT02030834). High tumor burden was defined as serum LDH higher than 1.5 folds the upper normal limit at infusion. In this cohort, we observed a trend toward higher CAR-T19 expansion in patients with high disease burden (n = 7, 18.9%) than in patients with low tumor burden (n = 30, 81.1%) (CAR19 copies/μg of DNA 35,857 vs 18,718 respectively; p = 0.1501). P-values are calculated with a two-sided unpaired student’s t-test.
