A Prospective, Open-label, Single-center, Single-arm Phase II Clinical Study of Cadonilimab (AK104) Combined With Monotherapy Chemotherapy in Patients With Advanced Non-small Cell Lung Cancer With Negative Driver Genes and Failed Immunotherapy

Inclusion Criteria:

Voluntarily participate in clinical research; Fully understand and be informed of this study and sign the informed consent form;

1. Age ≥ 18 and ≤ 75, male or female;
2. ECOG physical performance score of 0-2;
3. Patients with histologically confirmed squamous or non-squamous advanced non- small cell lung cancer (according to AJCC, 8th edition);
4. Patients who tested negative for driver genes after genetic testing;
5. Patients who have undergone previous systemic therapy and failed anti-PD-1/PD- L1 immunotherapy;
6. Presence of at least one measurable lesion as defined by Recist criteria 1.1;
7. Liver function: Total serum bilirubin ≤ 1.5 × ULN; For subjects without liver metastasis, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5 × ULN, and for those with liver metastasis, ALT and AST ≤ 5 × ULN;
8. Renal function: Serum creatinine ≤ 1.5 × ULN or creatinine clearance rate ≥ 45 mL/min (using the Cockcroft/Gault formula); Blood routine: Absolute neutrophil count ≥ 1.5 × 109/L, platelet count ≥ 70 × 109/L; Hemoglobin ≥ 80g/L (no blood transfusion or use of hematopoietic stimulating drugs for correction within 7 days before screening) with an expected lifespan of more than 3 months.

Exclusion Criteria:

1. ECOG physical performance score \> 2;
2. Previous treatment with bispecific antibodies;
3. Participation in other clinical trials within 30 days prior to screening;
4. Tumor metastasis to the brain and/or leptomeninges;
5. History of other malignancies (excluding cervical carcinoma in situ or skin basal cell carcinoma that has been cured, and other malignancies that have been cured for more than 5 years);
6. Accompanied by other serious diseases, including but not limited to:

   1. Difficult-to-control congestive heart failure (NYHA class III or IV), unstable angina, poorly controlled arrhythmia, uncontrolled moderate to severe hypertension (SBP \> 160mmHg or DBP \> 100mmHg);
   2. Severe active infection;
   3. Difficult-to-control diabetes (referring to large fluctuations in blood sugar despite standard insulin therapy and frequent blood glucose monitoring, affecting the patient's life and frequently causing hypotension);
   4. Mental illness affecting informed consent and/or protocol compliance.
7. Allergy to the drugs used in this protocol or their ingredients;
8. Pregnant (confirmed by blood or urine HCG testing) or breastfeeding women, or subjects of reproductive age who are unwilling or unable to take effective contraceptive measures (applicable to both male and female subjects) until at least 6 months after the last experimental treatment;
9. Investigators consider it inappropriate to participate in this study;
10. Unwilling to participate in this study or unable to sign the informed consent form.