Hepatic decompensation is the major driver of mortality in patients with HCC treated with atezolizumab plus bevacizumab: The impact of successful antiviral treatment

Background&aims: Unlike other malignancies, hepatic functional reserve competes with tumour progression in determining the risk of mortality from hepatocellular carcinoma (HCC). However, the relative contribution of hepatic decompensation over tumour progression in influencing overall survival (OS) has not been assessed in combination immunotherapy recipients. Approach&Results : From the AB-real observational study(n=898), we accrued 571 patients with advanced/unresectable HCC, Child-Pugh A class treated with frontline atezolizumab+bevacizumab(AB). Hepatic decompensation and tumour progression during followup were studied in relationship to patients’ OS using time-dependent Cox model. Baseline characteristics were evaluated as predictors of decompensation in competing risks analysis. During a median follow-up of 11.0 months (95%CI 5.1-19.7), 293 patients(51.3%) developed tumour progression without decompensation and 94(16.5%) developed decompensation. In multivariable time-dependent analysis, decompensation(hazard ratio[HR] 19.04, 95%CI 9.75-37.19), HCC progression(HR 9.91, 95%CI 5.85-16.78), albumin-bilirubin(ALBI) grade 2/3(HR 2.16, 95%CI 1.69-2.77) and number of nodules>3(HR 1.63, 95%CI 1.28-2.08) were independently associated with OS. Pre-treatment ALBI grade 2/3(subdistribution HR [sHR] 3.35, 95%CI 1.98-5.67) was independently associated with decompensation, whereas viral aetiology was protective(sHR 0.55, 95%CI 0.34-0.87). Among patients with viral aetiology, effective antiviral treatment was significantly associated with lower risk of decompensation (sHR 0.48, 95%CI 0.25-0.93). Conclusions: Hepatic decompensation identifies patients with the worst prognosis following AB and is more common in patients with baseline ALBI>1 and non-viral aetiology. Effective antiviral treatment may protect from decompensation, highlighting the prognostic disadvantage of patients with non-viral aetiologies and the importance of multi-disciplinary management to maximise OS.