A Study of Atezolizumab in Combination With Bevacizumab Compared With Sorafenib in Patients With Untreated Locally Advanced or Metastatic Hepatocellular Carcinoma

Inclusion Criteria:

* Locally advanced or metastatic and/or unresectable Hepatocellular Carcinoma (HCC)
* No prior systemic therapy for HCC. Previous use of herbal therapies/traditional Chinese medicines with anti-cancer activity included in the label is allowed, provided that these medications are discontinued prior to randomization.
* At least one measurable untreated lesion
* ECOG Performance Status of 0 or 1
* Adequate hematologic and end-organ function
* For women of childbearing potential: agreement to remain abstinent
* For men: agreement to remain abstinent
* Child-Pugh class A

Exclusion Criteria:

* History of leptomeningeal disease
* Active or history of autoimmune disease or immune deficiency
* History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, or idiopathic pneumonitis, or evidence of active pneumonitis on screening chest computed tomography scan
* Known active tuberculosis
* History of malignancy other than HCC within 5 years prior to screening, with the exception of malignancies with a negligible risk of metastasis or death
* Pregnancy or breastfeeding, or intention of becoming pregnant during study treatment or within at least 5 months after the last dose of atezolizumab, 6 months after the last dose of bevacizumab, or 1 month after the last dose of sorafenib
* Known fibrolamellar HCC, sarcomatoid HCC, or mixed cholangiocarcinoma and HCC
* Untreated or incompletely treated esophageal and/or gastric varices with bleeding or high-risk for bleeding
* A prior bleeding event due to esophageal and/or gastric varices within 6 months prior to initiation of study treatment.
* Moderate or severe ascites
* History of hepatic encephalopathy
* Co-infection of HBV and HCV
* Symptomatic, untreated, or actively progressing central nervous system (CNS) metastases
* Uncontrolled tumor-related pain
* Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures
* Uncontrolled or symptomatic hypercalcemia
* Treatment with systemic immunostimulatory agents
* Inadequately controlled arterial hypertension
* Prior history of hypertensive crisis or hypertensive encephalopathy
* Evidence of bleeding diathesis or significant coagulopathy
* History of intestinal obstruction and/or clinical signs or symptoms of GI obstruction including sub-occlusive disease related to the underlying disease or requirement for routine parenteral hydration
* Serious, non-healing or dehiscing wound, active ulcer, or untreated bone fracture
* Metastatic disease that involves major airways or blood vessels, or centrally located mediastinal tumor masses
* Local therapy to liver within 28 days prior to initiation of study treatment or non-recovery from side effects of any such procedure
* Chronic daily treatment with a non-steroidal anti-inflammatory drug (NSAID)