Introduction: CAR T has transformed the treatment landscape for hematologic malignancies. Despite its clinical success, access to CAR T remains limited due to complex infrastructure and intensive monitoring typically in inpatient (IP) settings at authorized treatment centers (ATCs) often located in large urban areas. There is a growing effort to expand CAR T access to more sites across the US, and this has led to an increase in new ATCs – many without Foundation for the Accreditation of Cellular Therapy (FACT) accreditation at launch – and an increase in outpatient (OP) CAR T administration. This study evaluated the characteristics and short-term clinical outcomes of patients treated with CAR T in the IP or OP setting at new US ATCs without FACT accreditation during the analysis period.

Methods: This was a retrospective database analysis using nationally representative administrative claims data from Medicare Fee-For-Service (FFS), managed Medicaid, and commercial payers. Adult patients (≥18) who received CAR T between 1/1/2024 and 1/31/2025 at a new ATC, authorized on or after 1/1/2024 (8 sites) without FACT accreditation at the time of infusion, and had ≥28 days of continuous medical coverage post-infusion were included. Demographics and baseline clinical characteristics were assessed on or before CAR T infusion date. Patients were followed for 28 days post-CAR T infusion. The following outcomes were assessed during follow-up: subsequent IP admissions, length of inpatient stay (LOS), intensive care unit (ICU) utilization, emergency room (ER) visits, cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), infection/fever, and death. Descriptive statistics were generated and stratified by setting of care (IP vs OP) and diagnosis (large B-cell lymphoma [LBCL] vs multiple myeloma [MM]).

Results: Among 38 total patients, mean (SD) age was 66.1 (14.0) years, 85.3% with known race/ethnicity were White, 57.9% male, and 76.3% insured by Medicare FFS. Mean (SD) number of other comorbidities was 1.3 (1.5), most commonly: congestive heart failure, diabetes, and chronic obstructive pulmonary disease.

Almost half (47.4%) of patients received CAR T in the OP setting. Mean (SD) number of comorbidities was slightly higher among IPs vs OPs (1.6 [1.6] vs 1.1 [1.3]). Among IPs, mean [SD] LOS for the CAR T stay was 19.1 [9.2] days. Less than half of OP CAR T patients were later admitted IP, and less than a third of IPs were readmitted subsequent to their initial CAR T stay. Among those with subsequent admission, mean (SD) LOS for the subsequent admission was longer for original IPs (18.8 [6.4] days) vs original OPs (12.1 [6.6] days). Over half (55.0%) of IPs utilized the ICU during or post-CAR T compared to less than a third of OPs. In both settings, few patients (<15%) had an ER visit. Nearly all (95%) IPs had observed CRS compared to less than half of OPs; in both settings, less than 15% of those with CRS had observed grade 3+. Similarly, 70.0% of IPs had observed ICANS compared to less than a quarter of OPs; about half of patients with ICANS in both settings had observed grade 3+. Most (85.0%) of IPs had observed infection/fever compared to <40% of OPs. No patients died during follow-up.

Over half (55.3%) of included CAR T patients had LBCL, 28.9% had MM, and the remaining had follicular lymphoma, mantle cell lymphoma, or acute lymphoblastic leukemia. Stratifying by LBCL vs MM, the mean (SD) number of baseline comorbidities was similar between diagnoses (1.2 [1.4] vs 1.2 [1.5]). More patients with MM received CAR T in OP than did patients with LBCL. Among IPs, mean (SD) LOS for CAR T administration was longer for patients with LBCL than patients with MM (17.8 [7.0] vs 12.3 [3.8] days). More patients with LBCL than MM also had observed CRS (71.4% vs <60%), ICANS (57.1% vs < 40%), and infection/fever (72.2% vs <50%).

Conclusions: This study provides initial insight into the clinical outcomes of patients treated with CAR T in the IP or OP setting at newly established ATCs without FACT accreditation during the analysis period. Both IP and OP CAR T administrations were shown to be feasible at these sites as well as treatment for all currently indicated diagnoses. Possible reasons for the lower incidence of adverse events among OPs in this study compared to IPs may be because providers are better at identifying suitable candidates for OP therapy and implementing early intervention strategies.

This content is only available as a PDF.
2025
Sign in via your Institution