Introduction: The efficacy of CAR T-cell therapy is well-established. However, the comparative hospital system costs and HRU for CAR T-cell therapy and SCT are largely unknown or based on rough estimates of cost-charge ratios. This study describes and compares the actuarial hospital costs and HRU of CAR T-cell therapy, administered in authorized treatment centers, and SCT for the procedure, pre-procedure, and follow-up periods. Methods: Adult patients in the PINC AI™ Healthcare Database were included if they had an inpatient or outpatient visit between 01/01/ 2017-04/30/2021 with CAR T-cell infusion or SCT transfusion for treating LBCL (principal or secondary discharge ICD-10-CM diagnosis codes: C83.3x, C85.1x, C85.2x, C85.8x, C83.8x, and C83.9x). Patients were excluded if they 1) had ≥2 CAR T-cell and/or SCT infusions, or 2) the treating hospital did not have continuous data for the patients during the 365-day pre-procedure and 180-day follow-up periods. The inpatient or outpatient infusion visit was considered the index event. Based on the index procedure, patients were classified as being in a CAR T-cell, autologous SCT (auto-SCT), or allogenic (allo-SCT) group. Patient characteristics (pre-index through index) and treating hospital characteristics (index) were summarized. Heath resource utilization (HRU) and costs (2021 US dollars) for the index, pre-procedure, and follow-up periods were assessed and reported by procedure type. Results: A total of 852 patients (208 CAR T; 595 auto-SCT; 49 allo-SCT) were treated at 37 hospital systems across the US. The mean patient age was 60 years (SD=12; median=62; 39.6% ≥ 65 yrs). 38.6% of patients were female, and 76.8% were white. Healthcare coverage varied (commercial: 43.9%; Medicare:36.3%; Medicaid:11.6%; other: 8.2%). The most common comorbidities other than malignancy were diabetes (17.6%), chronic pulmonary disease (9.2%), and renal disease (6.6%). Key patient characteristics (age, sex, race, health coverage, comorbidity) were similar across procedure types (Table 1). There was no noticeable difference in treating hospitals' teaching status nor hospital size between CAR T-cell therapy and SCT cohorts. Most patients were treated at large (n=608; 71.4%), teaching (n=720; 84.5%) hospitals; 93.4% (n=796) received their procedures inpatient, with slightly more auto-SCT in the inpatient than CAR T-cell infusions (94.8% vs 89.9%; p=0.01). Total mean cost of index procedure was higher for CAR T-cell therapy than for SCT ($371,136 CAR T, $96,515 auto-SCT, $169,269 allo-SCT; p<0.001). However, the mean index non-pharmacy cost was lower for CAR T-cell therapy than SCT (mean $41,375 CAR T, $51,778 auto-SCT, $111,594 allo-SCT; p<0.001). Among inpatient-treated patients, the average length of stay (LOS) was shorter for CAR T-cell therapy than for auto-SCT or allo-SCT (mean [median]: 18[15] days CAR T; 21[20] days auto-SCT; 28[26] days allo-SCT; p<0.001). Total ICU cost was lower for CAR T-cell therapy than for allo-SCT (mean $86,755 CAR T, $86,497 auto-SCT, $191,980 allo-SCT; p<0.001). Details of the index procedure hospital costs and HRU outcomes for CAR T, auto-SCT, and allo-SCT are in Table 2. Assessment of other outcomes, including adverse events, costs and HRU during the pre- and post-index periods, and sensitivity analysis are ongoing. Conclusions: This study is the first to examine actuarial cost and HRU with most recent real-world use of CAR-T and SCT using the hospital system perspective. The total and pharmacy cost to hospital providers for the index procedure were higher for patients who received CAR T-cell therapy than for SCT patients. However, non-pharmacy cost incurred during index procedure was lower for CAR T-cell therapy. Shorter hospital stays for CAR T-cell therapy patients contributed to this cost differential. Even though CAR T-cell treated patients incurred higher upfront pharmacy costs to hospitals compared to SCT, there were non-pharmacy cost offsets and lower HRU burdens overall to hospital system. Results should be interpreted with caution because they may not reflect HRU and costs to hospitals not included in the PINC AI™ Healthcare Database. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal