This study is testing a new medicine called AZD5851 for a type of liver cancer called hepatocellular carcinoma (HCC). The study is for adults with advanced or recurrent HCC who have a specific marker called GPC3+ on their cancer cells. This marker helps doctors see if the cancer is of a certain type. Participants must have tried other treatments that did not work or were too hard to handle. The study will see if AZD5851 is safe and how well it works. It will also study how the body reacts to the medicine. People joining the study need to have a good liver function score, called Child-Pugh Grade A, and must be managing any infections they have, like hepatitis.

Key Points:

• This study is open-label, meaning both doctors and participants know they are getting AZD5851.
• Participants should not have had recent serious infections or certain past treatments.
• Joining means agreeing to regular check-ups and tests during the study.