OBJECTIVE: Although chimeric antigen receptor T cell therapy is generally administered in the inpatient setting, opportunities exist for treatment in the outpatient setting to reduce costs. Post-infusion costs for liso-cel by site of care may differ between the United States (US) and other countries. This analysis assessed post-infusion monitoring costs by site of care among US patients with LBCL treated with liso-cel as a second-line therapy in the TRANSFORM study (NCT03575351).

METHODS: Individual patient-level case report forms detailing health care resource utilization (HCRU) among patients receiving liso-cel were analyzed. A 2-step micro-costing methodology identified HCRU and estimated associated costs using a 6-month time horizon, beginning with the date of liso-cel infusion. First, HCRU in the 6-month timeframe post-infusion was calculated. Next, costs were applied to each HCRU. Unit costs were measured from the health care system perspective, using peer-reviewed literature and public sources, and adjusted to 2021 US dollars. Analyses were stratified by administration site.

RESULTS: Among 56 patients treated with liso-cel in TRANSFORM, 39 (70%) and 17 (30%) patients were classified as inpatients and outpatients, respectively. Estimated mean (median) 6-month total post-infusion monitoring costs (excluding liso-cel acquisition) were $96,436 ($67,169) and $51,823 ($42,172) for inpatients and outpatients, respectively, a difference of $44,613 ($24,997). Facility costs were the primary driver of costs in both settings. Among all patients, median (range) total length of stay (LOS) was shorter for outpatients than inpatients (0 [0‒21] vs 11 [0‒80] days). Among 8 (47%) outpatients who were hospitalized, median (range) time from liso-cel infusion to first inpatient admission was 18 (2‒160) days; median (range) total LOS was 9 (4‒21) days.

CONCLUSIONS: In US outpatients treated with liso-cel, lower costs and reduced LOS were observed when compared with inpatients. This study illustrates potential cost savings and reduced HCRU with outpatient administration of liso-cel in TRANSFORM.