The time toxicity of CAR-T cell therapy for non-Hodgkin's lymphoma

Abstract

Abstract Introduction: Chimeric Antigen Receptor T-cell (CAR-T) therapy has revolutionized the treatment landscape for many types of non-Hodgkin's lymphoma (NHL), offering the potential for prolonged remission and even cure in relapsed/refractory disease. Despite being a one-time treatment, patients spend a significant number of days in contact with the healthcare system in the preparation, monitoring and follow-up required for safe administration. Time toxicity describes the burden on patients' time required to receive all care associated with treatment. This study seeks to characterize the number of healthcare contact days (the so-called time toxicity) associated with CAR-T cell therapy for NHL. Methods: We conducted a claims database analysis of healthcare contact days using the OptumLabs platform. Patients who received CAR-T were identified using a combination of ICD-10-Procedure Coding System (PCS) codes, Current Procedural Terminology (CPT)/revenue codes and Healthcare Common Procedure Coding System (HCPCS) codes. NHL diagnosis was confirmed using ICD-10 codes (C82.X, C83.X and C85.X) to include diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL) or other NHL subtype. All claims indicating a healthcare contact day were captured in the time between apheresis and administration and at 1 month, 3 months and 1 year following CAR-T administration. Patients were excluded from analysis if they did not have continuous coverage with available claims data within the periods of interest. Negative binomial regression was used to estimate incident rate ratios (IRR), adjusting for demographic and clinical factors. Results: A total of 813 patients received CAR-T cell therapy for NHL between October 2017 and December 2024. The mean age of patients was 64.4 (range 18-87 years); 64.7% of patients were male, and 79.3% of patients received CAR-T inpatient. Median length of follow-up from CAR-T administration to coverage end or death was 340 days (IQR 164-639 days). Eleven patients (1.4%), 54 patients (6.6%), and 205 patients (25.2%) died in the 1 month, 3 months, and 1 year following CAR-T, respectively. DLBCL was the most common NHL subtype (86.0%) followed by MCL (6.8%), other NHL subtype (4.1%) and FL (3.2%). Patients received axi-cel (32.1%), liso-cel (21.2%), brexu-cel (9.7%), tisa-cel (4.7%) or unspecified CAR-T product (32.4%). Between apheresis and CAR-T administration, patients spent a median of 7 days (IQR 5-11 days) or 23.7% of days with healthcare contact (n=470). At 1 month after CAR-T, patients spent a median of 20 days (IQR 16-25 days) or 67.2% of days with healthcare contact (n=806). At 3 months, patients spent a median of 28 days (IQR 22-38 days) or 31.5% of days with healthcare contact (n=773). At 1 year, patients spent a median of 52 days (IQR 37-72 days) or 18.9% of days with healthcare contact (n=591). Outpatient CAR-T administration was associated with lower time toxicity at all timepoints compared to inpatient administration (p<0.05). FL and MCL had lower time toxicity only at the 1-year mark compared to DLBCL (FL IRR 0.72, 95% CI 0.57-0.90, p<0.01, MCL IRR 0.74, 95% CI 0.57-0.97, p=0.03). Brexu-cel was associated with higher time toxicity at all timepoints compared to liso-cel (p<0.05). Axi-cel was associated with higher time toxicity at 1 month (IRR 1.08, 95% CI 1.01-1.15, p=0.03) and 3 months (IRR 1.20, 95% CI 1.08-1.34, p<0.01), but not at 1 year when compared to liso-cel (IRR 1.09, 95% CI 0.91-1.30, p=0.35). Conclusions: Patients receiving CAR-T cell therapy for NHL spent a significant number of days in contact with the healthcare system, particularly in the first month following administration. Time toxicity lessened over time but patients still spent nearly 20% of their days with healthcare contact in the year following CAR-T. Outpatient administration was associated with significantly lower time toxicity. FL and MCL had lower time toxicity at 1 year compared to DLBCL, likely due to selection for surviving patients. Axi-cel and brexu-cel were associated with higher time toxicity when compared to liso-cel, reflecting the increased toxicity profiles of these products. These findings help clinicians and patients understand their true time commitment beyond the first month and can potentially inform future innovations for patient-centered delivery of cellular therapy that decrease time toxicity and improve patient quality of life.