Key Inclusion Criteria:

          1. Recurrent, locally advanced or metastatic solid tumor cancer excluding the following:
             MSI-low colorectal cancer, glioblastoma multiforme, prostate cancer, pancreatic
             cancer, mucosal and ocular melanoma.

          2. Receipt of all standard therapies for the tumor type

          3. Measurable (target) disease by iRECIST

          4. If of childbearing potential (male or female), agrees to practice an effective form of
             contraception during study treatment and for at least 3 months following last
             treatment

          5. Willingness to undergo a pre-treatment and on-treatment biopsy, if required

        Key Exclusion Criteria:

          1. History of severe hypersensitivity reactions to other monoclonal antibodies.

          2. Previous treatment with any anti-CD27 antibody.

          3. Inadequate washout period from prior therapy as defined in the Protocol.

          4. Patients who have received more than 0 or 1 prior PD-1/PD-L1 inhibitor depending on
             their tumor type

          5. Major surgery within 4 weeks prior to study treatment.

          6. Use of immunosuppressive medications within 4 weeks or systemic corticosteroids within
             2 weeks prior to study treatment.

          7. Other prior malignancy, except for adequately treated basal or squamous cell skin
             cancer or in situ cancers. For all other cancers, the patient must be disease-free for
             at least 3 years to be allowed to enroll.

          8. Thrombotic events within the last 6 months prior to study treatment

          9. Active, untreated central nervous system metastases.

         10. Active autoimmune disease or documented history of autoimmune disease.

         11. History of (non-infectious) pneumonitis or has current pneumonitis.

         12. Active diverticulitis

         13. Known infection of HIV, Hepatitis B, or Hepatitis C.

        There are additional criteria your study doctor will review with you to confirm your
        eligibility for the study.