Tremelimumab (tremelimumab-actl; Imjudo) is a monoclonal antibody and immune checkpoint inhibitor (ICI) that blocks cytotoxic T lymphocyte-associated antigen-4 (CTLA-4). A single, priming dose of intravenous tremelimumab is used in combination with durvalumab, an ICI that blocks programmed cell-death ligand 1, in a regimen known as STRIDE (Single Tremelimumab Regular Interval Durvalumab). STRIDE is approved for the treatment of adults with unresectable hepatocellular carcinoma (HCC) in the USA and Japan and for the first-line treatment of adults with advanced or unresectable HCC in Europe. In the phase III HIMALAYA trial, STRIDE significantly improved overall survival (OS) compared with sorafenib in adults with unresectable HCC and no prior systemic therapy. A higher proportion of STRIDE versus sorafenib recipients had an objective response to treatment. The OS benefit associated with STRIDE was sustained with 4 years' follow-up. STRIDE had a manageable safety profile that differed from that of sorafenib. Grade 3 or 4 treatment-related adverse events occurred in a lower proportion of STRIDE versus sorafenib recipients. Based on the available evidence, tremelimumab used as part of the STRIDE regimen is a valuable first-line agent that expands the treatment options available to patients with advanced or unresectable HCC.