A Phase III, Randomised, Open-label, Sponsor-blinded, Multicentre Study of Rilvegostomig in Combination with Bevacizumab with or without Tremelimumab as First-line Treatment in Patients With Advanced Hepatocellular Carcinoma

Inclusion Criteria: - Locally advanced or metastatic and/or unresectable HCC - WHO/ECOG performance status of 0 or 1 - BCLC stage B (that is not eligible for locoregional therapy) or stage C. Child-Pugh Score class A - At least one measurable target lesion - co-infected with HBV and HCV are not eligible - Adequate organ and bone marrow function measured during the screening period - Must not have received prior systemic therapy for intermediate, advanced, or metastatic HCC. - Disease that is not amenable to curative surgical and/or locoregional therapies. For participants who received locoregional therapy for HCC, locoregional therapy must have been completed ≥ 28 days prior to the baseline scan for the current study. Exclusion Criteria: Medical condition - Any evidence of uncontrolled intercurrent diseases - Active or prior documented autoimmune or inflammatory disorders requiring chronic treatment with steroids or other immunosuppressive treatment - History of another primary malignancy - Persistent toxicities caused by previous anti-cancer therapy excluding alopecia, not yet improved to Grade ≤ 1 or baseline. - Clinically meaningful ascites, pleural effusion, or pericardial effusion requiring non-pharmacologic intervention to maintain symptomatic control within 6 months prior to the first scheduled dose. - History of active primary immunodeficiency or active infection - History of hepatic encephalopathy - Current or recent (within 10 days of first dose of study treatment) use of aspirin (≥ 325 mg/day) or treatment with dipyridamole, ticlopidine, clopidogrel, and cilostazol - Current or recent (within 10 days prior to study treatment start) use of full-dose oral or parenteral anticoagulants or thrombolytic agents for therapeutic (as opposed to prophylactic) purposes is ineligible Bleeding or other risks HCC related - Known fibrolamellar HCC, sarcomatoid HCC, or mixed cholangiocarcinoma and HCC. - Central nervous system metastases or spinal cord compression (including asymptomatic and adequately treated disease) - Prior treatment with anti-CTLA-4 and/or anti-TIGIT. - Radiotherapy within 28 days and abdominal/ pelvic radiotherapy within 60 days prior to initiation of study treatment, except palliative radiotherapy to bone lesions within 7 days prior to initiation of study treatment