A Real-World Comparison of CAR T-Cell Therapy Versus a Historical Standard-of-Care Approach for Relapsed-Refractory Large B-Cell Lymphoma in Ontario, Canada

• Published in: Blood 2024-11, Vol.144 (Supplement 1), p.5134-5134
• Main Authors: Kordbacheh, Tiana, Prica, Anca, Chan, Kelvin KW, Aminilari, Mahmood, Ante, Zharmaine, Liu, Ning, Gong, Inna Y, Bhella, Sita, Crump, Michael, Vijenthira, Abi, Kuruvilla, John, Kridel, Robert, Chen, Christine I, Kukreti, Vishal, Yang, Chloe, Malik, Nauman, Hodgson, David, Rodin, Danielle
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2024-206375

Background Anti-CD19 Chimeric Antigen Receptor T-cell (CAR-T) immunotherapies have been funded in Canada for patients with relapsed-refractory large B-cell lymphoma (RR LBCL) after two lines of systemic therapy since December 2019. However, real-world evidence of CAR-T outcomes has been limited to small series with little comparison to prior standard-of-care management. We compared overall survival (OS), adverse events, and healthcare utilization for a cohort of patients with RR LBCL consecutively treated with CAR-T versus a cohort of historical controls treated with standard-of-care therapy prior to CAR-T approval. Methods This is a propensity-weighted retrospective cohort study of patients with RR LBCL treated at Princess Margaret (PM) Cancer Centre. Using linked clinical and administrative datasets, consecutive patients treated with CAR-T (2020-2022) following provincial funding approval were compared to a matched cohort of historical controls (2012-2017). Patients were followed from index date, defined as the date of progression following 2 lines of chemotherapy (2L) in the historical controls and following last therapy (2L or higher) in the CAR-T patients for up to 3-years, with maximum follow-up to March 31, 2023. Stabilized inverse probability treatment weighting (sIPTW) was used to account for confounding between cohorts (age, sex, lactate dehydrogenase, and comorbidities). Kaplan meier curves and IPTW-weighted Cox proportional hazard regression analyses estimated the adjusted hazard ratio (HR) between treatment cohort and OS. A landmark survival analysis of patients alive at 3 months post-index date addressed immortal time bias. Adverse events (AEs) from inpatient/emergency department [ED] diagnoses and healthcare utilization were reported per 1000 person-days at risk. Results A total of 86 CAR-T patients and 150 historical control patients were evaluable for comparison. Variables were balanced after applying the sIPTW (based on standardized difference