Inclusion Criteria:

          1. Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1 at
             enrollment

          2. Histological or cytological confirmation of advanced NSCLC who progressed following
             platinum-based chemotherapy.

          3. Confirmation of measurable disease based on RECIST 1.1 by investigators

          4. No prior exposure to immune-mediated therapy .

          5. In dose escalation phase, 6 DLT evaluable patients whose tumor cell PD-L1 expression
             less than 25% will be enrolled in each cohort. In dose expansion phase, 45 patients
             with confirmed PD-L1-positive NSCLC by the Ventana SP263 IHC assay will be enrolled

          6. All patients must be able to provide an available tumor sample taken ≤3 years prior to
             screening

          7. Adequate organ and marrow function

          8. Must have a life expectancy of at least 12 weeks

          9. Body weight >30 kg

        Exclusion Criteria:

          1. History of allogeneic organ transplantation.

          2. Active or prior documented autoimmune or inflammatory disorders

          3. Uncontrolled intercurrent illness, including but not limited to, ongoing or active
             infection, symptomatic congestive heart failure .

          4. History of another primary malignancy

          5. History of active primary immunodeficiency

          6. Brain metastases or spinal cord compression.

          7. QT interval corrected for heart rate using Fridericia's formula (QTcF) ≥450 ms in male
             and ≥470 ms in female

          8. Known allergy or hypersensitivity to any of the study drugs or any of the study drug
             excipients

          9. Receipt of the last dose of anticancer therapy (chemotherapy, endocrine therapy,
             targeted therapy, biologic therapy, tumor embolization, or monoclonal antibodies) ≤ 3
             weeks prior to the first dose of study drug

         10. Radiotherapy with a limited field of radiation for palliation within 1 week of the
             first dose of study treatment

         11. Receipt of live attenuated vaccine within 30 days prior to the first dose of IP.

         12. Major surgical procedure

         13. Current or prior use of immunosuppressive medication within 14 days.

         14. The prohibited medications

         15. Participation in another clinical study with an investigational product administered
             in the last 30 days

         16. Judgment by the Investigator that the patient should not participate in the study if
             the patient is unlikely to comply with study procedures, restrictions, and
             requirements.