A Study Evaluating The Efficacy and Safety of Neoadjuvant Immunotherapy Combinations in Patients With Surgically Resectable Hepatocellular Carcinoma

Inclusion Criteria: * Diagnosis of HCC confirmed either histologically or clinically according to AASLD criteria for patients with cirrhosis. For participants without cirrhosis, histological confirmation is mandatory. * HCC that is amenable to R0 surgical resection with curative intent in the opinion of the surgeons and oncologists or hepatologists involved in the care of the participant. Patients presenting with resectable HCC within or beyond Milan criteria (without extrahepatic spread or macrovascular invasion) are eligible. * Measurable disease (at least one target lesion) according to RECIST v1.1 as determined by the investigator * Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1 within 7 days prior to randomization * Child-Pugh Class A within 7 days prior to randomization * Negative HIV test at screening * No prior locoregional or systemic treatment for HCC * Adequate hematologic and end-organ function * Documented virology status of hepatitis * For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraception * For men: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraception, and agreement to refrain from donating sperm General Exclusion Criteria: * Presence of extrahepatic disease or macrovascular invasion * Known fibrolamellar HCC, sarcomatoid HCC, mixed cholangiocarcinoma and HCC, or other rare variants of HCC * History of hepatic encephalopathy if clinically significant within one year prior to initiation of study treatment * Moderate or severe ascites * Active co-infection with HBV and HCV * Known active co-infection with HBV and hepatitis D viral infection * Prior treatment with CD137 agonists or immune checkpoint inhibitors, including anti-CTLA-4, anti-PD-1, and anti-PD-L1 therapeutic antibodies * Treatment with investigational therapy within 28 days prior to initiation of study treatment * Untreated or incompletely treated esophageal and/or gastric varices with bleeding or that are at high risk for bleeding * A prior bleeding event due to esophageal and/or gastric varices within 6 months prior to initiation of study treatment * Inadequately controlled hypertension * History of hypertensive crisis or hypertensive encephalopathy * Significant vascular disease within 6 months prior to initiation of study treatment * History of hemoptysis within 1 month prior to initiation of study treatment * Evidence of bleeding diathesis or significant coagulopathy * Current or recent (\<= 10 days prior to initiation of study treatment) use of full-dose oral or parenteral anticoagulants or thrombolytic agents for therapeutic purposes * History of abdominal or tracheoesophageal fistula, GI perforation or intra-abdominal abscesses within 6 months prior to initiation of study treatment * History of intestinal obstruction and/or clinical sign or symptoms of GI obstruction * Serious, non-healing or dehiscing wound, active ulcer, or untreated bone fracture * Grade \>= proteinuria * Major surgical procedure, open biopsy, or significant traumatic injury, or abdominal surgery, interventions or traumatic injuries, or anticipation of need of major surgical procedure other than potentially curative liver resection * Chronic daily treatment with a non-steroidal anti-inflammatory drug (NSAID) * Serious infection requiring oral or IV antibiotics and/or hospitalization * Active tuberculosis