Study to Assess the Safety, Tolerability, and Efficacy of IDX-1197 in Combination with XELOX or Irinotecan in Patients with Advanced Gastric Cancer

This study tests the safety, tolerability, and effectiveness of an investigational drug called IDX-1197 combined with standard chemotherapy regimens in patients with advanced stomach or gastroesophageal junction cancer that has not been previously treated or has progressed after two or more prior treatments. **You may be eligible if:** - You have advanced or metastatic gastric (stomach) or gastroesophageal junction cancer - You either have had no prior treatment for metastatic disease, or you have received two or more prior lines of treatment - Your cancer has at least one measurable lesion - Your overall health status is adequate (ECOG performance status 0 or 1) **You may NOT be eligible if:** - You have brain metastases or cancer spread to the membranes around the brain - You have HER2-positive cancer (applies to the first-line group) - You have uncontrolled diabetes, serious infection, severe heart or lung disease, or high blood pressure - You have HIV, active hepatitis B or C, or a history of a myelodysplastic syndrome - You are taking certain medications that interact with the study drug (CYP3A4 inhibitors/inducers) Talk to your doctor to see if this trial is right for you.