Outpatient Administration of Chimeric Antigen Receptor T-Cell (CAR-T) Therapy for Non-Hodgkin Lymphoma (NHL), in a Large Multi-Center Network

Background Patients receiving CAR T-cell therapy for NHL are often hospitalized and need close monitoring for cytokine release syndrome (CRS) and neurotoxicity (ICANS). There is increasing interest to administer CAR-T in the outpatient setting due to a growing need for this treatment, limited inpatient capacity and to enhance patient satisfaction. The Sarah Cannon Transplant and Cellular Therapy Network (SCTCTN) has an established outpatient CAR-T program using standardized patient eligibility criteria, clinical pathways, quality standards, and a centralized remote patient monitoring (RPM) platform. Outlined is the he SCTCTN experience. Methods 273 NHL patients received an FDA approved CAR-T product through September 2023 at 5 SCTCTN sites. Patients received CAR-T in an outpatient (N=127; 4 sites) or inpatient setting (N=146; 1 inpatient only site and at 4 sites prior to establishment of outpatient programs). In programs administering outpatient therapy, patients receive lymphodepletion and CAR-T infusion in clinic followed by routine clinic visits up to day +30. Based upon the product administered, dexamethasone may have been administered for the first 3 days of infusion. Results Table 1. represents patient characteristics. Among patients who received CAR-T in the inpatient setting, axicabtagene ciloleucel (axi-cel) was the most commonly used product in 71% of patients. Axi-cel was more often used (41%) in the outpatient setting, although lisocabtagene marleucel (liso-cel) was also administered 29% of the time compared to 3% inpatient administration. There were significant differences in ethnicity, HCT Comorbidity Index score, and insurance status among patients who received inpatient vs. outpatient CAR-T. There was no difference in grade 3-4 CRS (8% vs. 6%) and grade 3-4 ICANS (7% vs. 4%) by site of administration. Similarly, there was no difference in the median doses of tociluzimab used between the two groups. As expected, the median days of hospitalization were significantly higher in patients receiving inpatient CAR-T compared to those receiving outpatient therapy (15 vs. 4 days, respectively). After excluding 8 patients where the cause of death could not be ascertained, overall mortality at 1-year post-infusion was 23% and 13% in the two groups, respectively. For both groups, the most common cause of mortality at 1 year was asoociated with disease relapse. Conclusion Through standardized inclusion/exclusion criteria, outpatient management guidelines, and support via remote patient monitoring, outpatient CAR T-cell therapy for NHL patients is a viable option. Toxicity management is possible without evidence that outpatient care adversely affects clinical outcomes. Selection of favored cell products as well as consistent use of prophylactic dexamethasone may support reduction in morbidity and warrant further investigation.