A Study of GSK5764227 in Combination With Standard of Care (SoC) or Other Agents in Participants With Advanced Solid Tumors

This trial is testing a new drug called GSK5764227 combined with standard chemotherapy for people with advanced colorectal cancer (Cohort A) or advanced prostate cancer (Cohort B) that hasn't responded to earlier treatments. **You may be eligible if...** - You are in good physical condition (ECOG 0 or 1) - You have advanced colon or rectal cancer (Cohort A) or advanced prostate cancer (Cohort B), confirmed by biopsy - Your organ function is adequate - You have not had major surgery in the past 4 weeks **You may NOT be eligible if...** - You have another cancer that is active or was treated in the past 2 years (except certain skin cancers or fully treated in-situ cancers) - You have had serious bleeding or infection within the past weeks - You have untreated brain metastases - You have active interstitial lung disease or a history of severe pneumonitis - You have an autoimmune disease requiring systemic treatment in the past 2 years - You are on long-term immune-suppressing medications Talk to your doctor to see if this trial is right for you.