Impact of Etiology on Efficacy Outcomes with Atezolizumab Plus Bevacizumab in Patients with Advanced Hepatocellular Carcinoma: A Multinational Retrospective Analysis in Asia-Pacific.

Background: Atezolizumab-bevacizumab is a standard first-line treatment for unresectable hepatocellular carcinoma (uHCC). Given the diversity in HCC etiology and its potential impact on the tumor microenvironment, understanding how different liver disease etiologies affect treatment efficacy is important.

Objective: We assessed the influence of liver disease etiology on the efficacy of atezolizumab-bevacizumab and evaluated changes in liver function during treatment with atezolizumab-bevacizumab.

Patients and methods: This study included 390 patients with uHCC treated with first-line atezolizumab-bevacizumab from Asan Medical Center, South Korea, and National Cancer Centre Singapore, Singapore from July 2016 to March 2023. Patients were classified to viral, metabolic dysfunction-associated liver disease (MASLD) and nonviral/non-MASLD groups. Albumin-bilirubin (ALBI) scores were recorded at baseline and every two cycles up to cycle six and at the time of disease progression.

Results: The majority of patients presented with viral etiologies (74.1%), and 17.2% had MASLD. Across etiological groups (viral versus MASLD versus nonviral/non-MASLD) no significant differences in objective response rate (23.2% versus 29.9% versus 23.5%, respectively; p = 0.515), progression-free survival (median 5.4 versus 7.7 versus 6.0 months; p = 0.320), and overall survival (18.1 versus 18.9 versus 14.4 months; p = 0.400) were observed. Among the patients with disease progression, ALBI scores at the time of progression were significantly higher than at baseline. Subsequent therapy was administered significantly less often to patients with ALBI grade 3 at disease progression compared with those with ALBI grades 1 or 2 (48.4% versus 78.8%, p = 0.002) CONCLUSIONS: Atezolizumab-bevacizumab demonstrates consistent efficacy regardless of HCC etiology, supporting its use as a first-line treatment across diverse patient populations. Liver function assessments remain crucial for managing therapy and predicting outcomes.