Atezolizumab plus bevacizumab (A+B) as first-line systemic therapy for advanced hepatocellular carcinoma (HCC): A multi-institution analysis of patient outcomes based on Child Pugh (CP) and ALBI liver function.

4099 Background: A+B is standard of care for advanced HCC in the first line setting, although was only evaluated in patients with CP class A liver function in IMbrave150. We sought to determine outcomes of patients in the real-world setting. Methods: We conducted a multi-institution retrospective analysis of patients with HCC who received A+B as first-line systemic therapy between March 2018 and November 2023, at Mayo Clinic and University Hospitals Seidman Cancer Center. Treatment response was evaluated, and progression free survival (PFS) and overall survival (OS) were determined using the Kaplan Meier method. Multivariate analyses were performed using Cox proportional hazard regression method. Results: Among patients with HCC (n=322), 226, 86, and 10 had CP-A, -B, and -C liver function, while 120, 177, and 25 had ALBI grade 1, 2, and 3 liver function. Median age was 66.5 years, 78.6% were male, and 82.6% were white. Liver disease causes included hepatitis B (5.3%) and C (34.8%), ethanol use (26.1%), and non-alcoholic steatohepatitis (15.5%). Macrovascular invasion was seen in 42.9%, and 30.4% had extrahepatic metastatic disease. Median OS for patients with CP-A5/6 was 21.6 months, B7 (n=49) was 9.1 months, and B8-C12 was 4.7 months ( p<0.0001). Median OS by ALBI grade was 34.9, 11.7, and 4.7 months for grades 1, 2, and 3. Median PFS was 8.9, 6.4, and 2.7 months for CP-A5/6, B7, and B8-C12 ( p<0.0001). Median PFS by ALBI grade was 11.0, 6.4, and 3.7 months for grades 1, 2, and 3 ( p=0.0001). Among patients with CP-A, those with ALBI grade 1 had mOS of 34.9 months versus 14.2 months for those with grade 2. Partial response was seen in 29.2%, 19.8% and 10.0% of patients with CP-A, -B, and -C, while 32.7%, 33.7%, and 40.0% had stable disease. In a univariate analysis, factors predictive of shorter OS included CP-B7 or CP-B8-C12, ALBI grade 2 or 3, hepatitis B, poorer ECOG performance status (PS), macrovascular invasion, non-white race, and lack of prior surgery or embolization. In multivariate analyses, CP score, ALBI grade, hepatitis B, ECOG PS, and macrovascular invasion were significantly associated with survival. There was significant interaction between CP and ALBI grade (Table). Conclusions: A+B remains a viable option in patients with CP-B7 liver function, although benefit is significantly less than those with CP-A. ALBI score has predictive value and can identify two prognostic groups among those with CP-A liver function. Table: see text