Study of Ociperlimab (BGB-A1217) in Combination With Tislelizumab in Advanced Solid Tumors

Key Inclusion Criteria:

Phase 1 Key Inclusion Criteria

1. Had Eastern Cooperative Oncology Group (ECOG) Performance Status less than or equal to (\<=) 1.
2. Greater than or equal to (\>=) measurable lesion per RECIST v1.1.
3. Had adequate organ function.
4. Phase 1- Participants with histologically or cytologically confirmed advanced, metastatic, unresectable solid tumors who had previously received standard systemic therapy or for which treatment is not available, not tolerated or refused.

Phase 1b Key Inclusion Criteria

1. Signed informed consent form (ICF) and able to comply with study requirements.
2. Age \>= 18 years (or the legal age of consent) at the time the ICF was signed.
3. Histologically or cytologically confirmed tumor types in the following disease cohorts:

   Cohort 1: stage IV squamous NSCLC Cohort 2: stage IV non-squamous NSCLC Cohort 3: stage IV squamous or non-squamous NSCLC with PD-L1 positive. Cohort 4: extensive-stage SCLC Cohort 5: stage IIIB, IIIC or IV NSCLC Cohort 6: stage IV ESCC Cohort 7: stage IV EAC Cohort 8: recurrent or metastatic HNSCC incurable by local therapies Cohort 9: stage IV G/GEJ adenocarcinoma. Cohort 10: stage IV squamous or non-squamous NSCLC with PD-L1 positive.
4. ECOG Performance Status \<= 1
5. Adequate organ function
6. Were willing to use highly effective method of birth control

Phase 1 Key Exclusion Criteria:

1. Active brain or leptomeningeal metastasis.
2. Active autoimmune diseases or history of autoimmune diseases that could have relapsed.
3. Had severe chronic or active infections requiring systemic antibacterial, antifungal or antiviral therapy, including tuberculosis infection, etc. (antiviral therapy is permitted for patients with hepatocellular carcinoma).
4. Concurrent participation in another therapeutic clinical trial.
5. Received prior therapies targeting TIGIT.

Phase 1b Key Exclusion Criteria:

1. Participants with any prior therapy for recurrent/metastatic disease.
2. Non-squamous NSCLC patients with sensitizing epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) fusion, and c-ros oncogene 1 (ROS1) fusion.
3. Gastric cancer participants with squamous or with positive HER2 expression.
4. Prior therapy with any drug specifically targeting T-cell co-stimulation or checkpoint pathways. (anti-PD(L)1 exception for Cohort 5).
5. Active leptomeningeal disease or uncontrolled brain metastasis.
6. Active autoimmune diseases or history of autoimmune diseases that may relapse.
7. With severe chronic or active infections requiring systemic antibacterial, antifungal or antiviral therapy, including tuberculosis infection, etc. (antiviral therapy is permitted for participants with hepatocellular carcinoma).
8. Concurrent participation in another therapeutic clinical study.

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