A Study of CS1001 in Subjects With Stage IV Non-Small Cell Lung Cancer

Inclusion Criteria:

1. Willing to participate in this trial; fully understand and informed of this trial, and able to provide written informed consent form (ICF).
2. 18-75 years of age (18 and 75 included) on the day of signing ICF.
3. Histologically or cytologically confirmed stage IV non-small cell lung cancer (staged according to the 8th International Association for the Study of Lung Cancer (IASLC) classification.
4. Subjects haven't received systemic treatment for advanced/metastatic NSCLC.
5. Measurable target lesion evaluated by investigators according to RECIST v1.1.
6. ECOG PS of 0-1.
7. Life expectancy ≥ 12 weeks.
8. Subject with prior anti-cancer treatment can only be enrolled when all toxicities except for hearing loss, alopecia and fatigue, of prior anti-cancer treatment has recovered to ≤ Grade 1 according to National Cancer Institute [NCI] Common Terminology Criteria for Adverse Events (CTCAE) v4.03.
9. Subjects must have adequate organ function.
10. Women of childbearing potential (WOBPC, as defined in section 13.5) must have a negative pregnancy test ≤7 days prior to the first dose of investigational product. WOBCP or fertile men and their WOBCP partners must agree to use an effective method of birth control from providing signed ICF and for 6 months after last dose of investigational product.

Exclusion Criteria:

1. Histologically confirmed small cell lung cancer or containing small cell component.
2. Subjects with current active autoimmune disease or prior history of autoimmune disease.
3. Malignancies other than NSCLC within 5 years prior to randomization.
4. Known history of human immunodefiency virus (HIV) infection and/or acquired immune deficiency syndrome.
5. Subject with active hepatitis B or hepatitis C.
6. Subjects with known history of alcoholism or drugs abuse.
7. Has a known hypersensitivity to any component of study treatment, for example pemetrexed, cisplatin, carboplatin or other platinum compounds.
8. Subjects with other conditions that in the investigator's opinion may influence subject's compliance or make subjects not suitable for participating in this trial.