Study on the Safety and Initial Effectiveness of GSK5460025 Alone or with Other Cancer Treatments in Patients with Solid Tumors

Inclusion Criteria

• Have an advanced solid tumor that cannot be removed by surgery, has spread, or has come back.
• Have a specific genetic status (dMMR/MSI-H) confirmed by a lab test, or be willing to have this status tested.
• Provide a sample of the tumor tissue, either from a previous biopsy or a new one.
• Plan to use GSK5460025 as the next treatment option.
• Be in relatively good health with an ECOG performance status of 0 to 2.
• Have a life expectancy of at least 3 months.
• Have good organ function as specified in the study.

Part 1 inclusion criteria:

• Have an advanced solid tumor and have tried all standard treatment options.

Part 2 inclusion criteria:

• Have advanced colorectal or endometrial cancer.
• Have received 1 to 3 previous cancer treatments, including at least one immune therapy.
• Have at least one measurable tumor during the screening period.

Exclusion Criteria

• Have not fully recovered from side effects of previous cancer treatments.
• Have previously been treated with a Werner inhibitor or NERT agent.
• Cannot swallow pills or keep them down.
• Have untreated or worsening cancer in the brain or central nervous system.
• Have another cancer that has progressed or needed treatment in the last 2 years, except for certain skin cancers or in situ cancers that have been removed.
• Have digestive issues that could affect how the study drugs are absorbed.
• Have liver cirrhosis or unstable liver or bile duct disease.
• Have allergies to any of the study drugs or their ingredients.