Summary
The purpose of this study is to find out if a new drug, called IDRX-42 (also known as GSK6042981), is effective in treating adults with a type of cancer called Gastrointestinal Stromal Tumours (GIST) when compared to another drug named sunitinib.
The study will see if IDRX-42 works well and is safe for people whose GIST has spread (metastatic) or cannot be surgically removed (unresectable), and who have already taken the drug imatinib.