• Sign a written informed consent before implementing any trial-related procedures.

• Age ≥ 18 years and ≤ 70 years, male or female.

• Histologically or cytologically confirmed inoperable locally advanced (IIB-IIIC) NSCLC (International Association for the Study of Lung Cancer and American Joint Committee on Cancer 8th edition TNM lung cancer staging);

• Notes:

‣ If EBUS/EUS or mediastinoscopy can safely obtain samples from the hilar or mediastinal lymph nodes, it is encouraged to obtain tissue for confirmation of involvement. When the lymph node boundary is clear and at least one lymph node has a short axis ≥ 2.0 cm, lymph node involvement can be determined by imaging (CT/MRI scan). For lymph nodes with a short axis \< 2.0 cm, if pathologically confirmed, the patient can be included in the study. If the primary tumor is deemed unresectable and mediastinal lymph node metastasis does not affect the radiotherapy plan, the patient can be included.

‣ Determined and documented by a multidisciplinary tumor board or consultation with a thoracic surgeon: the patient has inoperable stage IIB-IIIC NSCLC.

• No evidence of distant metastatic disease on diagnostic quality CT or MRI scans of the chest, abdomen, pelvis, and brain and/or whole-body fluorodeoxyglucose (FDG)-PET/CT, and classified as non-IV stage NSCLC (i.e., M0).

• Note: For pleural effusion present in both CT chest scan and frontal chest X-ray, a thoracentesis should be performed to confirm the pleural effusion is negative on cytology and is non-exudative. For patients who meet all other inclusion/exclusion criteria but are unable to undergo thoracentesis due to minimal pleural effusion, they may still be included in the study.

• Provide a sufficient amount of quality-controlled tumor tissue or cell wax blocks for the pathology department of the study center to test PD-L1 expression using the 22C3 antibody, with a PD-L1 TPS ≥ 20%; or a pre-screening PD-L1 TPS ≥ 20% result (regardless of the antibody used, including 22C3, SP263, SP142).

• At least one measurable lesion based on the Response Evaluation Criteria in Solid Tumors (RECIST 1.1) for use as a target lesion.

• No prior treatment for advanced/metastatic NSCLC (chemotherapy, targeted therapy, immunotherapy, or radiotherapy). Patients who have previously received systemic induction or neoadjuvant therapy (chemotherapy, immunotherapy) for stage IIB-IIIC NSCLC and are about to receive curative concurrent chemoradiotherapy can be included in the study.

• Patients who have previously received induction immunotherapy can be included, including the following therapies: anti-PD-1, anti-PD-L1, or anti-PD-L2 agents, or drugs targeting another co-stimulatory or inhibitory T-cell receptor (e.g., CTLA-4, OX-40, CD137), immune LAG-3 inhibitors, and TIGIT monoclonal antibodies.

• ECOG performance status of 0-1.

⁃ Life expectancy ≥ 6 months.

⁃ Adequate organ function, with the following laboratory parameters:

⁃ For women of childbearing potential, a negative urine or serum pregnancy test must be performed within 3 days prior to the first dose of study drug (Day 1 of Cycle 1). If the urine pregnancy test cannot be confirmed as negative, a serum pregnancy test is required. Non-childbearing potential women are defined as those who are at least 1 year post-menopausal, surgically sterilized, or have undergone a hysterectomy.

⁃ If there is a risk of pregnancy, all participants (regardless of sex) must use a contraceptive method with a failure rate of less than 1% during the entire treatment period and for 120 days after the last dose of the study drug (or 180 days after the last dose of chemotherapy).