Partial Inclusion Criteria:

          -  Patients with advanced or metastatic cancer who have received no more than 3 lines of
             prior systemic therapy for advanced/metastatic disease.

          -  Histologically diagnosed advanced (unresectable) or metastatic cancer with at least
             one measurable lesion as per RECIST 1.1

          -  Tumor lesions amenable for biopsy, if deemed safe by the investigator

          -  Toxicity from prior cancer therapy should resolve to CTCAE Grade ≤ 1 (excluding
             alopecia and neuropathy, where up to Grade 2 residual is allowed)

        Partial Exclusion Criteria:

          -  Prior treatment with immune checkpoint inhibitor (iCPI) (Note: this criterion does not
             apply to patients with melanoma)

          -  Receipt of any conventional or investigational systemic anti-cancer therapy within 26
             days prior to the start of study treatment

          -  Concurrent chemotherapy, immunotherapy, biologic, or hormonal anti-cancer therapy.
             Agents such as bisphosphonates or denosumab are acceptable as prophylaxis for bone
             metastasis.

          -  Patients must not have received a transfusion (platelets or red blood cells) within 4
             weeks of the first dose of study treatment

          -  Patients with an active, known or suspected autoimmune disease. Patients with type I
             diabetes mellitus, hypothyroidism only requiring hormone replacement, skin not
             requiring systemic treatment are permitted to enroll.

          -  Patients with known active hepatitis (e.g., hepatitis B or C) NOTE: Patients with
             previously treated hepatitis B or C are permitted to enroll if there is evidence of
             documented resolution of infection.

          -  Received a fecal transplant, spore or other preparation of fecal material, isolated
             bacterial products, genetically modified bacteria, or VE800