The goal of this phase II, open-label, single-arm study is to evaluate the efficacy and safety of induction immunotherapy and chemotherapy followed by the multidisciplinary team (MDT)-guided radiotherapy or surgery in unresectable, stage III non-small cell lung cancer.

Inclusion Criteria:

1.18 to 75 years old, both male and female;

2.ECOG score: 0-1;

3.Histopathologically or cytologically confirmed, stage III (AJCC 8th) non-small cell lung cancer;

4.Multidisciplinary team (MDT) discussion confirmed unresectable disease but can be treated by curative radiotherapy;

5.Measurable lesions available;

6.Major organ function is basically normal;

7.Estimated survival time is at least 6 months;

8.Non-surgically sterile female subjects of childbearing age must have a negative serum HCG test before inclusion.

Exclusion Criteria:

1. Histologically or cytologically confirmed mixed SCLC and NSCLC;
2. Subjects with driver gene mutations(EGFR mutation, ALK fusion, etc.);
3. Previous systemic anti-tumor therapy including immune checkpoint inhibitors for NSCLC;
4. Previous thoracic radiotherapy;
5. Subjects who participated in other clinical trials within 4 weeks or 5 drug half-lives(whichever is shorter) before the first dose;
6. Systemic immunostimulant therapy before the first dose;
7. Systemic immunosuppressive therapy before the first dose or were expected to require systemic immunosuppressive drugs during the study treatment;
8. Subjects with autoimmune diseases;
9. Other malignant tumors other than non-small cell lung cancer within 5 years before screening;
10. Known or suspected interstitial pneumonia;
11. Other moderate to severe lung diseases that may interfere with the detection or treatment of drug-related pulmonary toxicity and seriously affect respiratory function;
12. Severe cardiovascular and cerebrovascular diseases;
13. Clinically significant bleeding symptoms or significant bleeding tendency within 1 month before the first dose;
14. Arteriovenous thrombotic events within 3 months before the first dose;
15. Positive HIV test;
16. Active hepatitis B or C;
17. Evidence of active tuberculosis infection within 1 year before the first dose;
18. Serious infection within 4 weeks before the first dose;
19. History of attenuated live vaccination 28 days before the first dose or expected to receive attenuated live vaccination during the study;
20. Major surgeries other than diagnosis or biopsy within 28 days prior to the first dose;
21. Previous or planned allogeneic bone marrow transplantation or solid organ transplantation;
22. History of severe allergic reactions to other monoclonal antibodies/fusion proteins;
23. Allergic to any component of the randomized treatment regimen;
24. Female subjects who are pregnant, lactating, or planning to get pregnant during the study period;
25. Subjects who have a known history of psychotropic drug abuse, alcoholism, or drug abuse;
26. Presence of other conditions that, in the opinion of the investigator, would make participation in this clinical trial inappropriate.