HER2 Tumor Vaccine(First Affiliated Hospital Bengbu Medical College)

This is a single-arm, open-label, clinical study to evaluate the safety of HER2 tumor vaccine injection alone/in combination with standard of care chemotherapy in patients with HER2/neu overexpressing gastric or gastroesophageal junction (GEJ) adenocarcinoma.
The purpose of this study is to evaluate the safety and tolerability, antitumor activity, The immunoreactivity, pharmacokinetics and of HER2 tumor vaccine.