Efficacy of PD-1 Inhibitor Combination Therapy in Non-small Cell Lung Cancer Patients Who Have Not Achieved Major Pathologic Response After Neoadjuvant Immunotherapy: a Multicenter, Phase II Clinical Trial

Inclusion Criteria: 1. Subjects ≥ 18 years of age on the day of signed informed consent, male or female, and willing to follow study procedures; 2. ECOG score of 0 \~ 1; 3. Patients with resectable clinical stage II-IIIB (N2 only) NSCLC prior to neoadjuvant as assessed by the investigator (AJCC 8th ed.) and who are receiving 3 to 4 courses of standard PD-1 monoclonal antibody in combination with chemotherapy (platinum-containing two-agent chemotherapy) as neoadjuvant therapy during the neoadjuvant phase 4. Pathological evaluation of tumor for MPR (less than 10% residual tumor cells from the primary tumor) and specific remission rate (1 - residual tumor/primary tumor) 5. Subjects must have had complete resection of the NSCLC (no residual tumor and all surgical margins negative) 6. Histologically or cytologically confirmed squamous or non-squamous NSCLC. Exclusion Criteria: 1. Subjects who have undergone segmental lung resection or wedge resection only, and subjects who have not undergone systemic or lobe-specific lymph node dissection; 2. Postoperative treatment with off-protocol antitumor therapy (e.g., radiotherapy, chemotherapy, targeted therapy, other immunotherapies, etc.; antitumor herbal therapies require a 2-week washout period); 3. Severe grade 3 or higher irAE or severe organ damage during neoadjuvant immunotherapy; 4. Previous history of allogeneic bone marrow or organ transplantation; 5. Previous or current interstitial pneumonitis/lung disease requiring systemic hormone therapy; 6. Uncontrolled hypertension (blood pressure ≥150/90 mmHg at rest), with antihypertensive medications maintained at a stable dose for 7 days prior to the first dose of study drug; 7. Combination of other malignant tumors within 5 years prior to the first dose of study drug that require active treatment, except for tumors cured in the opinion of the investigator;