Clinical Study of Personalized mRNA Vaccine Encoding Neoantigen in Patients With Advanced Digestive System Neoplasms

A single arm, open-label pilot study is designed to determine the safety, tolerability and effectiveness of personalized mRNA tumor vaccine encoding neoantigen in Patients with advanced esophageal squamous carcinoma, gastric adenocarcinoma, pancreatic adenocarcinoma and colorectal adenocarcinoma