A Study Evaluating the Safety, Tolerability, and Initial Efficacy of Recombinant Human Anti-T-cell Immunoreceptor With Ig and ITIM Domains (TIGIT) Monoclonal Antibody Injection (IBI939) in Subjects With Advanced Malignant Tumors

Inclusion criteria

1. Able to understand and willing to sign the ICF. 2. Adults 18 years of age or older. 3. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. 4. Life expectancy at least 12 weeks. 5. Adequate organ and bone marrow function. Eligibility Criteria： 1. Previous exposure to any anti-TIGIT antibody. 2. Participate in another interventional clinical study, except for the observational (non-interventional) clinical study or the survival follow-up phase of the interventional study. 3. Any investigational drugs received within 4 weeks prior to the first study treatment. 4. Receive the last dose of anti-tumor therapy within 4 weeks before the first dose of study therapy. 5. Immunosuppressive drugs were used within 4 weeks prior to the first administration of the study drug. 6. Medication requiring long-term systemic hormones or any other immunosuppression therapy. 7. Major surgical procedures (craniotomy, thoracotomy, or laparotomy) or unhealed wounds, ulcers, or fractures were performed within 4 weeks prior to the first dose of study therapy. 8. Primary central nervous system (CNS) malignancy, or untreated/active CNS metastases, or leptomeningeal disease. 9. History of autoimmune disease , present active autoimmune disease or inflammatory diseases 10. Positive human immunodeficiency virus (HIV) test. 11. Active hepatitis B or C, or tuberculosis. 12. History of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation. 13. Known history of hypersensitivity to any components of the IBI939 or Sintilimab. 14. Pregnant or nursing females.