Comparative analysis of survival outcomes in infused versus not-infused patients with aggressive B-cell lymphoma referred for CART.

7056 Background: Chimeric antigen receptor T-cell therapy (CART) has changed the treatment paradigm for patients (pts) with relapsed/refractory (R/R) aggressive B-Cell Non-Hodgkin’s Lymphoma (B-NHL). Yet, not all referrals complete the full process from harvest to re-infusion. This study evaluated a large cohort of pts “referred yet not infused” with CART to identify barriers to care and compare outcomes between pts infused vs non-infused. Methods: This is a retrospective analysis of adult pts with R/R B-NHL referred to Northwestern University from 2016-2024 for consideration for CART. Demographics, disease characteristics, and lines of therapy were evaluated. Survival analysis assessed median progression free survival (mPFS) and overall survival (mOS) in months (mo) from 2 starting timepoints (1) date of relapse with last line therapy prior to CART referral, denoted as PFS1 and OS1, and (2) date of treatment with CART or alternative to CART after referral, denoted as PFS2 and OS2. Results: Of 196 pts, 157 (80%) received CART (infused) whereas 39 (20%) were referred, but did not proceed to CART (non-infused). Comparison of demographics/disease characteristics demonstrated differences in age and ethnicity (Table 1). For infused pts, median time from apheresis to infusion was 33 days (range 9-86) and 94 pts (60%) received bridging therapy. For non-infused pts, median time from CART referral to alternative treatment was 14.5 days (range 1-80), most commonly rituximab-lenalidomide, rituximab-gemcitabine-based therapy (n=6 for each, 15%), or polatuzumab-based therapy (n=3, 8%). Death from disease progression was the most common reason for non-infusion (n=25, 64.1%). Median follow-up was 19 mo in surviving pts. Infused pts had higher mPFS1 than non-infused pts (5.6 [95% CI 3.7-7.5] vs 1.8 mo [95% CI 1.3-2.3]; p=0.05). Median PFS2 showed no significant difference. Infused pts had a markedly higher mOS1 (45.9 [95% CI 20-72] vs 2.5 mo [95% CI 1.8-3.2]; p=0.001), and mOS2 (32.3 [95% CI 0.1-64.5] vs 2.4 mo [95% CI 1.9-2.9]; p=0.001). Conclusions: CART infused vs non-infused pts differed with respect to age and ethnicity. The most common reason for failure to infuse was death due to disease progression. Infused pts demonstrated similar PFS to non-infused pts treated with alternative therapy. However, infused pts had a markedly improved OS. Collectively, our results suggest that survival in R/R B-NHL may be optimized by adopting measures that ensure success of proceeding to CART. Baseline demographics and disease characteristics. Infused; N=157 Non-infused; N=39 P-value Median Age (range) 58.5 (22-85) 67 (35-85) 0.04 Sex: Female 55 (35%) 17 (44%) 0.98 Race: Caucasian 134 (85%) 36 (92%) 0.57 Ethnicity: Hispanic 11 (7%) 8 (21%) 0.04 IPI > 3 21 (15%) 7 (20%) 0.49 Cell of Origin: GCB 64 (53%) 23 (61%) 0.46 Primary Refractory 91 (60%) 26 (68%) 0.46