Inclusion Criteria:
1. Age ≥18 years old, male or female;
2. ECOG PS score 0-1;
3. The expected survival time is not less than 12 weeks;
4. Histologically or cytologically confirmed non-small cell lung cancer patients with unresectable locally advanced (stage III) (AJCC TNM staging, 8th edition);
5. Patients who are not candidates for EGFR, ALK, or ROS1 targeted therapy, as confirmed by histologic or cytologic specimens (with documented evidence of no EGFR sensitizing mutation, ALK gene rearrangement, or ROS1 gene fusion);
6. Patients with grade 2 or below radiation pneumonitis without disease progression after receiving platinum-based concurrent/sequential chemoradiotherapy;
7. First dose was administered on days 1-42 (up to 42 days) after completion of concurrent/sequential platinum-based chemoradiotherapy for grade ≤1 RP; Patients with grade 2 RP who were downgraded to less than grade 1 RP within 56 days (including 56 days) after concurrent/sequential chemoradiotherapy received the first medication, and consolidation chemotherapy after radiotherapy was not allowed during the period.
All toxic effects from previous antineoplastic therapy, except hearing loss, alopecia, and fatigue, had to have recovered to grade 1 or less (according to NCI CTCAE V5.0) or baseline levels to be eligible.
9\. Have not received any anti-CTLA-4, anti-PD-1, anti-PD-L1/2, anti-angiogenesis inhibitors, or anti-tumor vaccine therapy; 10. Provide or collect biopsy tissue or blood samples during the treatment for biomarker analysis according to the subjects' wishes; 11. Normal function of major organs and bone marrow; 12. Female subjects of childbearing potential had to have a negative serum or urine pregnancy test 72 hours before starting the trial and be willing to use a highly effective, medically approved contraceptive method for the duration of the study and for 90 days after the last dose of the trial drug; Male participants whose partner was a woman of childbearing potential agreed to use an effective method of contraception or to be surgically sterilized for the duration of the study and for 90 days after the last dose of the trial drug.
13\. The subjects voluntarily participated in this study, and signed the informed consent form. The compliance was good, and the efficacy and adverse reactions were followed up according to the protocol.
Exclusion Criteria:
1. Histological types of mixed small cell lung cancer and non-small cell lung cancer;
2. Disease progression after chemoradiotherapy; Had undergone major surgery within 28 days before the first dose of a study drug or was planned to undergo major surgery during the study (at the investigator's discretion); 3.
4\. Administration of live attenuated vaccine within 28 days prior to dose or planned for the duration of the study; 5. Participated in another clinical study within 28 days before the first use of a trial drug, and used any trial drug; 6. Grade ≥3 radiation pneumonitis caused by chemoradiotherapy; 7. Imaging (CT/MRI) showed that the tumor invaded the large blood vessels or had unclear boundaries with blood vessels; 8. Known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation; 9. Presence of any active autoimmune disease or a history of autoimmune disease with expected recurrence; 10. Congenital or acquired immune deficiency; 11. Suffering from an infectious disease that is poorly controlled; 12. Subjects requiring systemic treatment with corticosteroids (\>10mg/ day of prednisone or equivalent dose of the same hormone) or other immunosuppressive agents within 14 days before the first dose of the trial drug; 13. Cancer other than NSCLC in the past 5 years; 14. Evidence of past or current severe impairment of lung function, with forced expiratory volume in 1 second (FEV1) \<1.2L or DLCO\<50% of predicted value; 15. Grade II or above myocardial ischemia or myocardial infarction with poorly controlled arrhythmia; 16. Have poorly controlled hypertension; 17. Occurrence of arterial/venous thrombotic events (cerebral embolism, deep vein thrombosis, pulmonary embolism, etc.) within 6 months before the first dose; 18. Subjects with clinically significant bleeding symptoms or clear evidence or history of bleeding tendency within 3 months before the first dose; 19. Obvious hemoptysis symptoms within 30 days before the first dose or hemoptysis of 2.5mL or more per day; 20. Known hereditary or acquired bleeding and thrombophilia (e.g. hemophilia, coagulopathy, thrombocytopenia, hypersplenism, etc.); 21. Urine routine showed urine protein ≥ (++), or 24-hour urine protein ≥ 1.0g; 22. The need for systemic antibiotics due to infection within 14 days before the first dose of medication; Or unexplained fever \> 38.5 ° C 14 days before the first dose of medication; 23. Pregnant or lactating women; 24. Known allergy or intolerance to the study drug or its excipients; 25. Any condition that the investigator considers may harm the subject or cause the subject to be unable to meet or perform the requirements of the study.
