Real-World Analysis Compares Inpatient and Outpatient CAR T-Cell Therapy in MCL and Follicular Lymphoma

A retrospective analysis presented at the 2023 Transplantation & Cellular Therapy Meetings assessed inpatient vs outpatient administration of CAR T-cell therapy in patients with mantle cell lymphoma (MCL) and follicular lymphoma (FL). The analysis, which was based on real-world data, demonstrated similarities, as well as differences, in the outcomes of the different patient populations.

Specifically, inpatient infusion was linked with greater comorbidity burden and increased likelihood of adverse effects (AEs) in patients with FL who received CAR T-cell therapy, but not in those with MCL who also received the treatment.

To further understand the association between inpatient vs outpatient treatment on the outcomes of patients undergoing CAR T-cell therapy, it was found that in the real-world MCL (n = 151) and FL (n = 267) populations, median time from leukapheresis to CAR T-cell infusion was similar for MCL and FL in both infusion settings at 25 to 27 days. AEs were observed in 68% and 59% of patients with MCL and FL, respectively, within 30 days post-infusion. A total 20% to 25% of patients received CAR T-cell therapy infusions in outpatient settings.

As CAR T-cell therapies have garnered approvals in both the relapsed/refractory MCL and FL patient populations, there is a continued interest in optimal administration of this treatment option. CAR T-cell therapy is typically administered in the inpatient setting, but as the treatment continues to become more widely used in clinical practice, there is a renewed interest in utilizing the therapy in the outpatient setting.

The retrospective analysis included data rendered from April 2017 through March 2022. Here, investigators aimed to evaluate patients with MCL or FL with an index date for CAR T-cell treatment between October 2017 and December 2021, with a minimum of 180 days of pre-index and at least 90 days of post-index follow-up.

CAR T-cell options included brexucabtagene autoleucel (brexu-cel; Tecartus) or unspecified CAR T-cell agent for patients treated with MCL, and lisocabtagene maraleucel (liso-cel; Breyanzi), tisagenlecleucel (tisa-cel; Kymriah), axicabtagene ciloleucel (axi-cel; Yescarta), or an unspecified agent for patients with FL.

Patients were excluded from the study if they had been on any previous trials within 45 days prior to the CAR T infusion date or within 15 days following their infusion date. Additional exclusion criteria included a diagnosis of concurrent MCL and FL diagnoses or concurrent diagnosis of mediastinal large B-cell lymphoma, acute lymphoblastic leukemia, or diffuse large B-cell lymphoma are cause for exclusion; as well as prior treatment with liso-cel, tisa-cel, or axi-cel for those with MCL and prior therapy with brexu-cel for patients with FL.

Investigators aimed to determine patient characteristics, infusion setting, CAR T-cell therapy-associated AEs, and health resource utilization (HRU) of real-world CAR T-cell therapy use for patients with MCL and FL.

In the MCL cohort, 72% of the 151 patients were infused in the inpatient setting and 75% of patients overall were male. The mean age was 63.8 years old (+8.6) and 59% of patients were commercially insured; 31% had Medicare, 9% had Medicaid, and 3% had unknown/other insurance types. Of the 113 patients with observed AEs, 68% were infused in the inpatient setting vs 32% in the outpatient setting. Of the 38 patients who did not have AEs, 82% received treatment in the inpatient setting vs 18% in the outpatient setting.

In the FL cohort, 81% of patients were infused in the inpatient setting. Moreover, in this group, 64% of patients were male, the mean age was 61.4 years old (+10.3) and 70% were commercially insured; 20% had Medicare, 7% had Medicaid, and 3% had unknown/other insurance types.

Of the 182 patients with observed AEs, 82% were in the inpatient setting and 18% were infused in the outpatient setting. Additionally, of the 85 patients who did not have an AE, 79% were infused in the inpatient setting vs 21% in the outpatient setting. Twenty-six percent of patients with FL utilized treatment with axi-cel as their CAR T-cell therapy most often. The median time from leukapheresis to infusion was similar for inpatient settings at 27 days between both groups.

Among patients with MCL who received CAR T-cell therapy, 68% had an observed AE within 30 days of infusion, whereas 79% of outpatient-infused patients with MCL were hospitalized within 0 to 3 days and 88% within 0 to 30 days. Seventeen percent of patients required ICU care by day 30 within the MCL patient population due to an observed AE.

In those with FL, 59% had an observed AE within 30 days post-infusion. In the outpatient setting, 57% of these were hospitalized within 0 to 3 days and 80% within 0 to 30 days. Eighteen patients with an observed AE required ICU care by day 30.

In the outpatient setting for patients with MCL, 47% experienced CRS within 0 to 3 days of infusion and 47% of patients were subsequentially hospitalized within that period. Among the 108 patients with MCL who received inpatient infusion, 42% experienced CRS within 0 to 3 days and were also hospitalized.

Conversely, 10 of the 51 outpatient-infused patients with FL experienced CRS within 0 to 3 days and were hospitalized, whereas 64 of the 216 inpatient-infused patients with FL experienced CRS within 0 to 3 days and were hospitalized.

Additionally, 4 outpatient-infused patients with MCL experienced neurologic events within 0 to 3 days post-infusion. In the inpatient setting for patients with MCL, this rate was 10%. In the outpatient setting, 3 patients with FL experienced neurologic events within 0 to 3 days post-infusion compared with the 5% of patients observed in the inpatient-infused setting.

Patients with FL who exhibited a high number of comorbid conditions also had a greater likelihood of undergoing CAR T-cell infusion in the inpatient setting (OR, 1.33; 95% CI, 1.07-1.69; P <.05). It was also found that patients with FL who had more comorbidities were predictive of observed AEs that subsequentially occurred within 3 days following CAR T-cell infusion (HR, 1.16; 95% CI, 1.03-1.30; P <.05).

Study limitations include data being unavailable for some characteristics that influence AE incidence and choice of infusion setting are not captured in these data. Additionally, investigators noted that it is possible that AEs may be under identified, and identification may vary by infusion setting. Coding detail was also insufficient to support product-level analysis for FL.

Reference

Seyedin R, Hasegawa, Rajagopalan K, et al. Chimeric antigen receptor (CAR) T-cell therapy setting of care: a retrospective cohort analysis of MCL and FL patients in the United States (US). Presented at: 2023 Transplantation & Cellular Therapy Meetings; February 15-19, 2023; Orlando, FL. Poster 509.