Evaluation of Infigratinib in Patients With Locally Advanced or Metastatic Gastric Cancer or GEJ Adenocarcinoma

Inclusion Criteria: * 18 years and older * Histologically or cytologically confirmed locally advanced or metastatic gastric adenocarcinoma, or gastroesophageal junction adenocarcinoma. * Failed at least 2 lines of prior systemic therapy * Willing to undergo tumor biopsy or provide FFPE samples for central lab testing. * At least one measurable tumor lesion by RECIST v1.1 * Eastern cooperative oncology group (ECOG) performance status of 0 or 1. * Life expectancy ≥3 months. * Willing to participate in this study and sign informed consent form, able to read and understand the study, follow the procedures. Exclusion Criteria: * History of other primary malignancies within 3 years except adequately treated in situ carcinoma of the cervix or non-melanoma carcinoma of the skin or any other curatively treated malignancy that is not expected to require treatment for recurrence during the study. * Previous or current treatment of a mitogen-activated protein kinase (MAPK-MEK) or selective FGFR inhibitor. * Any known hypersensitivity to infigratinib or its excipients. * History and/or current evidence of extensive tissue calcification. * Current evidence of endocrine alterations of calcium/phosphate homeostasis. * Have impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of oral infigratinib (such as, ulcerative diseases, uncontrolled nausea, vomiting, diarrhea, malabsorption syndrome, small bowel resection).14. Laboratory abnormality as defined in protocol. * Considered unsuitable to participate in the study by Investigator