Phase II Study Comparing Regorafenib with Envafolimab Versus Physician-Selected Treatment in Adults with Metastatic Gastrointestinal Stromal Tumors Having KIT Exon 17 Mutations Resistant to Standard Therapy

What this Trial Is About

Gastrointestinal stromal tumors GISTs often result from mutations in the c-kit or PDGFRA genes and mainly develop in the stomach and small intestine. This research focuses on metastatic GISTs with KIT exon 17 mutations that have become resistant to standard treatments. The trial aims to evaluate the effectiveness and safety of combining the drug regorafenib with the immune therapy envafolimab, exploring how this combination might improve treatment outcomes by affecting the tumors immune environment. Participants will be randomly assigned to one of two groups. One group will receive regorafenib orally at 120 mg daily for three weeks followed by one week off, combined with envafolimab given by subcutaneous injection every two weeks. The other group will receive treatments selected by their physicians based on prior responses and genetic testing, either continuing previously effective targeted drugs or a combination of two drugs. Treatment continues until the disease worsens, side effects become intolerable, or the participant chooses to stop. Those enrolled will have imaging scans before starting treatment and then every two months to monitor progress. The study measures progression-free survival over up to two years, tracking how long participants remain free from disease worsening. Researchers will also assess safety and the relationship between the immune environment and treatment effectiveness. The study plans to include 100 patients and may last several years.

Comparing Regorafenib Combined With Envafolimab to Physician's Choice in Patients With Metastatic Gastrointestinal Stromal Tumors Harboring KIT Exon 17 Mutations Refractory to Standard Treatment