There is a growing number of patients diagnosed with gastrointestinal cancers who are also simultaneously being treated with GLP-1 Receptor Agonists (RA)s. To date, no clinical trial data exists to establish safety and/or feasibility with use of GLP-1 RAs during chemotherapy in the metastatic setting. The goal of this clinical trial is to evaluate the safety, tolerability, preliminary efficacy, and correlative analyses of combining GLP-1 RAs with standard chemotherapy in patients with metastatic pancreatic, colorectal, or hepatocellular cancers in the first-line setting.