Inclusion Criteria:  HER2-overexpressing advanced or metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma that has progressed on or after a prior HER2-directed agent and fluoropyrimidine- or platinum-containing chemotherapy (2nd-line or 3rd-line) Adequate Bone Marrow Function. Adequate Renal & Liver Function. Adequate Performance Status  Exclusion Criteria:  Patients with known symptomatic CNS metastases or leptomeningeal disease requiring steroids. Prior treatment with any anti-CD47 or anti-SIRPα agent. Prior treatment with ramucirumab.