Health State Utilities for Adverse Events Associated with Chimeric Antigen Receptor T-Cell Therapy in Large B-Cell Lymphoma

Background Chimeric antigen receptor (CAR) T-cell therapy provides effective treatment for large B-cell lymphoma (LBCL). Cost-utility analyses examining and comparing the value of these treatments require health state utilities representing key characteristics to differentiate among therapies. This study estimated utilities for adverse events (AEs) associated with CAR T-cell therapy, including cytokine release syndrome (CRS) and neurological events (NEs). Methods Health state vignettes were drafted based on literature review, AE reports from a trial of CAR T-cell therapy, and clinician input. Health states were valued in time trade-off interviews with general population participants in the UK. The first vignette described relapsed/refractory LBCL treated with CAR T-cell therapy without AEs. Five other vignettes had the same LBCL and treatment description, with the addition of an AE. Disutilities (i.e., utility decrease) associated with these AEs were calculated by subtracting the utility of the health state without AEs from those of the other health states. Results Interviews were completed with 218 participants (50% male; mean age 49 years). Mean (standard deviation [SD]) utility for CAR T-cell therapy without AEs was 0.73 (0.30). Mean (SD) disutilities associated with CRS were -0.01 (0.04) for grade 1, -0.05 (0.09) for grade 2, and -0.23 (0.24) for grade 3/4. Mean (SD) disutilities associated with NEs were -0.04 (0.07) for grade 1/2 and -0.18 (0.22) for grade 3/4. Conclusions More severe AEs were associated with greater disutilities. Health state utilities estimated in this study may be useful in cost-effectiveness models examining the value of CAR T-cell therapy in patients with LBCL.