Inclusion Criteria:

          -  Age ≥18 years.

          -  Have histologically or cytologically proven adenocarcinoma of the pancreas.

          -  Have previously treated metastatic disease.

          -  Have radiographic disease progression.

          -  Patients with the presence of at least one measurable tumor lesion.

          -  Patient's acceptance to have a tumor biopsy at baseline and on

          -  Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1

          -  Patients must have adequate organ and marrow function defined by study-specified
             laboratory tests.

          -  For both Women and Men, must use acceptable form of birth control while on study.

          -  Ability to understand and willingness to sign a written informed consent document.

        Exclusion Criteria:

          -  Known history or evidence of brain metastases.

          -  Had chemotherapy, radiation, or biological cancer therapy within the last 14 days.

          -  Have received an investigational agent or device within the last 28 days.

          -  Had surgery within the last 28 days.

          -  Expected to require any other form of systemic or localized cancer therapy while on
             study.

          -  Have received a vaccine within the last 14 days (7 days for the COVID vaccine) or
             received a live vaccine within the last 30 days.

          -  Have received steroids within the last 14 days.

          -  Use more than 4 g/day of acetaminophen.

          -  Use of organic nitrates.

          -  Use of guanylate cyclase (GC) stimulators such as riociguat.

          -  Consumption of substantial amounts of alcohol (≥5 units/day)

          -  Use of strong or moderate cytochrome P450 3A4 (CYP3A4) inhibitor or inducer.

          -  Patients on immunosuppressive agents within the last 7 days

          -  Known allergy to both penicillin and sulfa.

          -  Severe hypersensitivity reaction to any monoclonal antibody.

          -  History of severe hypersensitivity to tadalafil.

          -  Have implant(s) or device(s) that has not and cannot be easily removed.

          -  Have artificial joints or implanted medical devices that cannot be easily removed.

          -  Have any evidence of clinical or radiographic ascites.

          -  Have significant and/or malignant pleural effusion

          -  Uncontrolled intercurrent illness.

          -  Subjects with active, known or suspected autoimmune disease.

          -  Have a tissue or organ allograft, including corneal allograft.

          -  Have been diagnosed HIV, Hepatitis B or C positive.

          -  Is on supplemental home oxygen.

          -  Has an unhealed surgical wound or ulcer, or a bone fracture considered non-healing.

          -  Has clinically significant heart disease

          -  Prior history of non-arterial ischemic optic retinopathy.

          -  History of significant hypotensive episode requiring hospitalization within 6 months.

          -  Has insufficient peripheral vein access.

          -  Is unwilling or unable to follow the study schedule for any reason.

          -  Is pregnant or breastfeeding.