This is a phase 1, open-label study to evaluate the safety and tolerability of neoantigen personalized mRNA tumour vaccine combined with Adebrelimab (a PD-L1 humanized monoclonal antibody) in patients with surgically resected pancreatic adenocarcinoma.

Inclusion Criteria:

1. Voluntarily signed the informed consent form and complied with protocols requirements.
2. Patients with radiographically resectable primary pancreatic tumors with histopathology or cytology confirmed resected ductal pancreatic adenocarcinoma (PDAC) with macroscopic complete resection (R0 and R1).
3. Pancreatic cancer surgical staging per AJCC 8th edition staging: T 1-3, N0-2, M0.
4. Tumour specimen availability.
5. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
6. Life expectancy ≥ 6 months.
7. Surgical complications have recovered, or complications lower than Clavien-Dindo complication grade 3.
8. Adequate marrow and organ function.
9. Patients with fertility are willing to use an adequate method of contraception.

Exclusion Criteria:

1. Prior anti-PDAC therapy (e.g., chemotherapy, radiotherapy, targeted therapy, immunotherapy and therapeutic tumor vaccines) prior to initiation of study treatment.
2. Unsuitable for immunotherapy assessed by the investigator.
3. Plan to receive a live-attenuated vaccine within 28 days prior to initiation of study treatment or during the study treatment or within 90 days after the end of study treatment.
4. Have any active autoimmune disease, or have a history of autoimmune disease and have received systemic therapy in the past 2 years.
5. Active tuberculosis or a history of active tuberculosis infection within 28 days prior to initiation of study treatment.
6. Known or highly suspected history of interstitial pneumonia.
7. Allergic to research drug ingredients, or have a history of severe allergic reactions to other vaccines.
8. Prior malignancy within 5 years prior to study entry.
9. Known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation.
10. Known splenectomy history.
11. Concurrent severe infection within 28 days prior to initiation of study treatment.
12. Congenital or acquired immune deficiency.
13. Active hepatitis B (HBV-DNA≥1000IU/ml), hepatitis C (hepatitis C antibody positive, and HCV-RNA higher than the lower limit of assay).
14. Uncontrolled or severe cardiovascular disease.
15. Other situations that are not suitable for inclusion in this study judged by investigator.