Personalized Neoantigen Vaccine in Pancreatic Cancer Patients Following Surgical Resection and Adjuvant Chemotherapy

Inclusion Criteria： 1. Must freely sign informed consent; 2. Aged 18 to 70 years old; 3. Histologically or cytologically confirmed diagnosis of pancreatic adenocarcinoma; 4. Must provide all exons of tumor tissue sequencing data, transcriptome sequencing data and the peripheral blood of all exons sequencing data; 5. ECOG score is 0 or 1; 6. Completed an R0 or R1 surgical resection as determined by pathology； 7. Completion of at least 4 months of adjuvant chemotherapy with ticgio monotherapy or mFOLFIRINOX; 8. Completion of imaging records 1 week before personalized immunotherapy, including but not limited to full-body PET-CT and brain MRI, 9. The end of chemotherapy is followed by a one-week natural washout period； 10. Haematological index： * White blood cells ≥ 3500 / MCL * Lymphocytes \> 800/ MCL * neutrophils \> 1500/ MCL * Platelets \> 100000 / MCL * Hemoglobin \>10.0g/dL * Total serum bilirubin \<1.5× upper limit of normal value (ULN) * AST/ALT\<2.0 times the upper limit of normal * Serum creatinine \<1.5 times the upper limit of normal； 11. Pregnant, lactating women and women of child-bearing age must have a negative pregnancy test within 7 days before entering the group, and short-term have no fertility plan, and are willing to take protective measures (contraception or other birth control methods) before and during the clinical trial; 12. Good compliance, able to follow research protocols and follow-up procedures. Exclusion Criteria: 1. Evidence of disease recurrence or metastasis following surgical resection at any time prior to the first vaccination administration. 2. Diagnosed as other malignant tumor; 3. No neoantigen was found in the sequencing data; 4. There have been bone marrow or stem cell transplants; 5. Received systemic glucocorticoids with immunosuppressants; 6. Received other polypeptide inoculation 4 weeks before treatment; Patients may not be vaccinated with other polypeptides 8 weeks after the last individualized tumor targeted polypeptides trentment; 7. With HIV, HCV, HBV infection, severe asthma, autoimmune disease, immunodeficiency or treated with immunosuppressive drugs; 8. Uncontrolled complications include, but are not limited to, active infection, symptomatic congestive heart failure, unstable angina pectoris, and arrhythmias; 9. Infected with herpes virus (except those with scabs of more than 4 weeks)； 10. Infected with respiratory virus (except those who have recovered for more than 4 weeks); 11. Have severe coronary or cerebrovascular disease, or other conditions considered ineligible by the investigator; 12. Drug abuse. Clinical, psychological or social factor result in affecting informed consent or research implementation; 13. Have a history of drug or polypeptide allergies, or people who are allergic to other potential immunotherapies.