This research study is designed to evaluate the effects of a dendritic cell (kind of white blood cell) vaccine for pancreatic cancer.

This is a single arm open label trial that will assess the safety and tolerability of mature dendritic cell (mDC3/8) vaccine (primer and booster) in subjects with resected pancreatic adenocarcinoma.

Eligible patients that provide written informed consent will undergo apheresis to collect blood mononuclear cells for vaccine production approximately 1 week prior to vaccine infusion. Each study subject will receive cyclophosphamide 300mg/m^2 intravenously 3 to 4 days prior to the vaccine dose to deplete regulatory T cells. For each vaccine dose, all subjects will receive autologous dendritic cells pulsed with mutant KRAS peptides corresponding to the subject's specific tumor mutation and human leukocyte antigen type. On Day 1, the subject will receive the primer vaccine dose; this will be followed by one booster vaccine dose approximately 8 weeks later. Peripheral blood will be taken weekly, and a second apheresis procedure will be performed at the end of study to monitor the immune response to the vaccine. Information will be gathered from usual clinic visits for approximately 1 year following the End of Treatment Study Visit to evaluate for disease recurrence.

Inclusion Criteria:

• Pathologically-confirmed KRAS(G12D-), KRAS(G12V-), KRAS(G12R-) or KRAS(G12C-mutated) pancreatic ductal adenocarcinoma who are at high risk of relapse and have no evidence of disease.
• Expression of one or more of the following HLA class I alleles: HLA-A02, HLA-A03, HLA-A11, HLA-B07 and HLA-C08.
• Male or female, age 18+
• ECOG performance status 0-1
• Certain required laboratory values, performed within 14 days prior to consent
• Subjects of reproductive potential must agree to use a medically accepted birth control method during the trial and for at least two months following the trial.
• Provide written informed consent

Exclusion Criteria:

• Prior treatment with more than two lines of cytotoxic chemotherapy. Radiotherapy is not considered a line of therapy.
• Prior malignancy (except non-melanoma skin cancer) within 3 years.
• Pregnant or nursing women.
• Concurrent treatment with systemic immunosuppressants, including corticosteroids (e.g prednisone), calcineurin inhibitors (e.g tacrolimus, cyclosporine), antiproliferative agents (e.g mycophenolate mofetil, azathioprine) within 2 weeks of eligibility confirmation. Local (inhaled or topical) steroids or replacement dose prednisone (≤ 10 mg daily) are permitted.
• Known chronic viral infections including hepatitis B, hepatitis C, and HIV.
• Known allergy to eggs.
• Prior history of uveitis or autoimmune inflammatory eye disease.
• Uncontrolled intercurrent illness.
• Any condition that, in the opinion of the investigator, would interfere with evaluation of the investigational product or interpretation of subject safety or study results.