CAR T-Cell Therapy: Clinical Outcomes, Patient Selection and Financial Metrics with Tisagenlecleucel and Axicabtagene Ciloleucel, a Single Center Experience

Abstract

<h3>Background</h3> Axicabtagene ciloleucel (A) and Tisagenlecleucel (T) are FDA approved CAR T cell products that have changed treatment (tx) for patients (pts) w/ relapsed/refractory lymphoma. The high tx cost has implications in selection of pts for CAR T and data comparing these txs at a single institution is lacking. Here we report data for pts treated w/ A and T at OSUCCC. <h3>Methods</h3> 63 pts were included. 45 received A (1 under Expanded Access Protocol (EAP) for out of specification product) from 1/18-6/19 and 18 received T (8 pts under EAP) from 7/18-5/19. Fisher's exact test and Wilcoxon rank sum test were used to compare A and T pts, and Kaplan-Meier was used to estimate overall survival (OS) and progression-free survival (PFS). <h3>Results</h3> Pt differences, adverse events and tx characteristics are reported in Table 1. There were no differences in creatinine, ECOG, CRP nor most disease (dx) characteristics including dx type, primary refractory dx, marrow dx, history of auto, response prior to tx, and prior lines of tx. Dx stage was different (p=.03) with more A pts having stage III dx than T pts (47% vs. 17%) but less A pts having stage IV dx (44% vs. 61%). A pts had a lower number of double expressors (27% vs. 78%, p<.01). 7 A pts (16%) were infused outpatient (OP); all were admitted w/ a median time to admission of 1 day (range 0-4). 4 T pts (22%) were infused OP with 2 later admitted (1 pt after 2 days, the other after 6 days). 96% of A pts had Cytokine Release Syndrome (CRS) vs. 44% of T pts (p<.01). 73% of A pts had Neurotoxicity (NT) compared to 22% of T pts (p=.0004). Response at 6 months (p=0.32), OS (Fig. 1) and PFS (Fig. 2) were not significantly different. <h3>Conclusion</h3> Clinical outcomes (PFS & OS) were comparable between A and T. We observed a higher incidence of CRS and NT with A, similar to what was observed in clinical trials. Higher hospitalization cost and LOS was associated with A. Our conclusions are limited by small sample size and the retrospective nature of the study.