(B-163) Health Utilities in Unresectable Hepatocellular Carcinoma: Subgroups Analyses in the IMbrave150 Trial

Background: Health utilities are important outcome measures and prognostic indicators in unresectable hepatocellular carcinoma (HCC). The IMbrave150 trial assessed the efficacy and safety of atezolizumab plus bevacizumab (atezo-bev) versus sorafenib in patients with unresectable HCC. Here, we report the analyses of the health utilities for patients enrolled in the IMbrave150 trial to provide parameters for the economic evaluation of unresectable HCC.

Objectives: To determine how the disease severity, etiology, and with or without adverse events will affect the health utility scores among patients with unresectable HCC.

Methods: This study analyzed data from the IMbrave150 trial available through Vivli, including health-related quality of life (HRQoL) measurements from EQ-5D-5L, baseline characteristics (disease severity classified by The Barcelona Clinic Liver Cancer [BCLC] Staging System, etiology including hepatitis B virus [HBV], hepatitis C virus [HCV] and non-viral hepatitis, and with or without Vp4 invasion (presence of a tumor thrombus in the main portal vein invasion)), treatment regimens, and with or without adverse events (AE). We stratified subgroups by their baseline characteristics to observe health utility scores (range from 0 to 1) within different health states (progression-free survival [PFS], progressed disease [PD], end-of-life [EOL] and death). Specifically, to further evaluate how AE affects the utility score, we stratified the PFS by presence of grade 3 treatment-related AE (TRAE) or not. Health utility scores, derived from EQ-5D-5L weighting with the United States value set, were compared across these subgroups.

Results: We included 423 patients with unresectable HCC who received atezo-bev or sorafenib. Health utility declined as health deteriorated with the lowest health utility at EOL (PFS without AE: 0.819, PD: 0.809, EOL: 0.644). Patients with TRAE ≥grade 3 had lower utility score in PFS versus without AE (with TRAE: 0.789, without AE: 0.819). Among subgroups, lower health utilities were shown in BCLC stage C and Vp4 invasion compared with their counterparts in health states (BCLC stage C: PFS without AE 0.815, PFS with TRAE 0.762, PD 0.797, EOL 0.646; Vp4 invasion: PFS without AE 0.801, PFS with TRAE 0.774, PD 0.742, EOL 0.552). Stratified by disease etiologies, health utility in HBV was higher in PFS and PD but lower in EOL than HCV and non-viral hepatitis.

Conclusions: Disease severity, etiology, and severe adverse events influence health utilities for patients with unresectable HCC in different health states. The health utility scores estimated in this study could serve as crucial parameters for cost-effectiveness research of unresectable HCC.