This clinical trial is focused on studying a type of cancer known as Advanced Gastrointestinal Stromal Tumor (GIST). This is a rare cancer that occurs in the digestive tract, most commonly in the stomach or small intestine. The study is comparing two treatments: Ripretinib and Sunitinib. Ripretinib, also known by its code name DCC-2618, is a medication that targets specific proteins involved in cancer growth. Sunitinib is another medication used to treat certain types of cancer by blocking the action of proteins that promote tumor growth.

The purpose of the study is to compare the effectiveness of Ripretinib and Sunitinib in patients with advanced GIST who have specific genetic changes called KIT Exon 11 and Co-occurring KIT Exons 17 and/or 18 Mutations. These mutations are changes in the DNA that can affect how cancer grows and responds to treatment. Patients in this study have previously been treated with another medication called Imatinib but need further treatment due to the progression of their disease.

Participants in the study will be randomly assigned to receive either Ripretinib or Sunitinib. The study will last for a period of up to 24 months, during which time the patients will take the medication orally in the form of tablets or capsules. The progress of the disease will be monitored through regular medical assessments to determine how well the treatment is working. The study aims to provide valuable information on which treatment may be more effective for patients with this specific type of GIST.