This study is testing a new treatment for advanced liver cancer, called hepatocellular carcinoma (HCC). The treatment combines celecoxib, a pain-reducing drug, with durvalumab and tremelimumab, which are special proteins known as monoclonal antibodies. These antibodies help the body's immune system fight cancer cells. Patients will take celecoxib pills twice a day and receive the other two drugs through an IV (intravenous) on day 1 of a 28-day cycle. After the first cycle, only durvalumab is given while celecoxib continues.

• The study involves taking the medication for 28-day cycles and regular follow-up visits for up to 2 years.
• Participants must have measurable liver cancer and meet certain health criteria.
• Participants may need to undergo blood tests, imaging scans, and possibly a tissue biopsy.

This study aims to see if this combination can better treat liver cancer and examine the safety and effects on the body. Participants must be over 18 and willing to follow study procedures.