Key Inclusion Criteria:

1. Age ≥ 18 years.
2. Signed Informed Consent Form.
3. Histologically confirmed locally advanced or metastatic (Stage IIIB or IV) NSCLC of either squamous or non-squamous histology types with disease progression during or following treatment with at least one platinum-containing regimen, but no more than 2 lines of systemic therapy.
4. Participants must be able to provide fresh or archival tumor tissues for central assessment of PD-L1 expression in tumor cells. Participants with non-squamous histology must provide evidence of not harboring sensitizing epidermal growth factor (EGFR) mutation tested by a histology-based method.
5. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1.
6. Adequate hematologic and end-organ function.
7. Expected life span > 12 weeks.
8. Willing to be compliance with birth control requirement during pre-specified study participating period

Key Exclusion Criteria:

1. Prior therapies of docetaxel or treatment targeting programmed cell death protein 1 (PD-1), PD-L1 or cytotoxic T-lymphocyte associated protein 4 (CTLA-4).
2. Harboring EGFR sensitizing mutation or anaplastic lymphoma kinase (ALK) gene translocation.
3. Unresolved side effects of Grade 2 and above from prior anti-cancer therapies, except for adverse events (AEs) not constituting a likely safety risk (e.g. alopecia, rash, pigmentation, specific lab abnormalities).
4. History of severe hypersensitivity reactions to other monoclonal antibodies (mAbs).
5. History of interstitial lung disease, non-infectious pneumonitis or participants with significantly impaired pulmonary function, or who require supplemental oxygen at baseline.
6. With uncontrollable pleural effusion, pericardial effusion, or clinically significant ascites requiring interventional treatment.
7. Active leptomeningeal disease or uncontrolled, untreated brain metastasis.
8. Severe chronic or active infection requiring systemic treatment.
9. Known human immunodeficiency virus (HIV) infection, participants with untreated chronic hepatitis B, active vaccination treatment.
10. Insufficient cardiac functions and other underlying unfavorable cardiovascular conditions.
11. Prior allogeneic stem cell transplantation or organ transplantation.
12. Active autoimmune diseases or history of autoimmune diseases that may relapse.
13. With conditions requiring systemic treatment with either corticosteroids (>10 mg daily prednisone or equivalent) or other immunosuppressive medications.
14. With severe underlying medical conditions (including laboratory abnormalities) or alcohol or drug abuse that may affect the explanation of drug toxicity or AEs or result in impaired compliance with study conduct.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.