# Outpatient Versus Inpatient Administration of Ciltacabtagene Autoleucel in Multiple Myeloma: A Systematic Review of Clinical, Economic, and Humanistic Outcomes

## TL;DR

This study compares outpatient and inpatient administration of a CAR-T therapy for multiple myeloma, finding outpatient treatment may reduce hospital stays and costs without compromising safety or effectiveness.

## Contribution

The study systematically reviews clinical, economic, and quality-of-life outcomes of outpatient versus inpatient administration of cilta-cel for multiple myeloma.

## Key findings

- Outpatient cilta-cel showed high response rates (95% ORR) and favorable 1-year PFS and OS (86% and 96%).
- Outpatient treatment reduced hospital stays (median 4–6.5 days) compared to inpatient (median 19 days).
- Economic modeling suggested potential savings of ~$19,000 per outpatient-treated patient.

## Abstract

Ciltacabtagene autoleucel (cilta-cel) is a CAR-T treatment for relapsed/refractory multiple myeloma. It is often given in the hospital so clinicians can watch for side effects such as cytokine release syndrome and neurologic symptoms. Because these side effects with cilta-cel usually start several days after infusion, some centers are exploring giving it as an outpatient. In this systematic review, we gathered and summarized evidence on outpatient and inpatient cilta-cel administration, covering effectiveness, safety, healthcare resource use, costs, and quality-of-life outcomes. The findings suggest potential advantages of outpatient administration with respect to hospitalization, healthcare resource utilization and costs, while highlighting the need for further prospective and comparative studies to more comprehensively characterize clinical, economic, and patient-reported outcomes.

Background/Objectives: Ciltacabtagene autoleucel (cilta-cel) for relapsed/refractory multiple myeloma is typically administered inpatient (IP) to monitor for cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Because cilta-cel toxicities are typically delayed, outpatient (OP) administration (infusion and early monitoring) is being explored. We synthesized available evidence on OP and IP administration. Methods: MEDLINE, Embase, and Cochrane Library were searched from inception to 5 August 2025, supplemented by conference and gray literature searches. Eligible studies of adults with multiple myeloma receiving cilta-cel reported efficacy, safety, resource use, costs, and/or quality-of-life outcomes; findings were synthesized descriptively due to heterogeneity. Results: Seventy-four records (56 studies) were included; 90 patients received OP cilta-cel. OP clinical evidence (primarily three real-world studies) showed high response rates (ORR: 95%; median follow-up 4.6 months) and reported 1-year PFS and OS of 86% and 96%. In IP studies, median ORR was 91%, with median 1-year PFS 76% and median 1-year OS 85%. Any-grade CRS and ICANS occurred in 79–84% and 17–22% of OP patients (largely low grade); IP cohorts reported a median ICANS incidence of 17% (range 5–23%). Most OP patients were later hospitalized (86–93%), but stays were shorter (median 4–6.5 days) than in an IP cohort (median 19 days). Comparisons were unadjusted and may reflect selection differences. One modeling-based economic analysis estimated savings of ~$19,000 per OP-treated patient. Conclusions: OP cilta-cel appears feasible for selected patients and may reduce costs without compromising outcomes. Findings are descriptive and hypothesis-generating and prospective multicenter studies are needed to define long-term safety, durability, quality of life, and cost-effectiveness.