OBJECTIVES: Since 2017, CAR-T-cells therapy is a possible ≥3^rd line treatment for DLBCL in France. This study aimed at describing HCRU and costs in DLBCL patients treated by CAR-T-cells according to failure status.

METHODS: This was a descriptive, retrospective, longitudinal study using secondary data from French hospital database (PMSI). DLBCL patients treated by CAR-T-cells were identified over 2017-2020 period. Patients were followed-up for 6 months after CAR-T-cells administration or until inpatient death, whichever occurred first. Patients were classified according to whether or not they had a failure within 6 months after CAR-T-cells administration, defined as receiving a new therapy or an inpatient death. HCRU and costs were assessed monthly between 3 months before and 6 months after CAR-T-cells administration.

RESULTS: Among the 534 patients treated with CAR-T-cells, 362 had sufficient follow-up or a recorded inpatient death. Among them, 207 (57.2%) presented a failure. Ninety-five (45.9%) of them died during the follow-up period. Mean (±SD) ages were 59.1 (±11.7) and 60.6 (±11.2) years among patients with and without failure, respectively. Each month, 75% of patients in failure group had ≥1 hospitalization vs. 25 % in non-failure group. In failure group, 50% had ≥1 chemotherapy and 30% had ≥ 1 rituximab administration, monthly. Overall associated costs were similar before (≈€5,000) and during CAR-T-cells stay (≈€360,000) in both groups. From the 2^nd month post-CAR-T-cells administration, mean (±SD) hospital costs ranged between €4,775 (±6,110) and €6,621 (±10,414) in failure group, and between €750 (±2,719) and €2,149 (±15,218) in non-failure group.

This study presents limits related to claims databases and reflects the clinical practice in the first years of CAR-T availability, prior to last guidelines update.

CONCLUSIONS: Patients without failure within 6 months post CAR-T cells have close-to-zero monthly hospital costs. Meanwhile, patients with failure must be frequently hospitalized and treated, leading to greater healthcare costs.