A Study of Sequential Therapy of Camrelizumab Combined With Chemotherapy（Irinotecan Plus Platinum）and With Apatinib in Participants With Untreated Advanced Small Cell Lung Cancer（SCLC）

Inclusion Criteria

1. Extensive small cell lung cancer diagnosed by pathology or cytology.

2. Patients with extensive stage small cell lung cancer who have not previously beentreated for tumors (including radiotherapy, chemotherapy, use of similar VEGFRinhibitors and immune checkpoint inhibitors).

3. The disease progress of the patients with limited SCLC who had receivedchemotherapy/radiotherapy before, and no further treatment more than 6 months afterthe last chemotherapy/radiotherapy.

4. Expected survival≥3months.

5. Eastern Cooperative Oncology Group (ECOG) performance status 0-1.

6. Subjects enrolled must have measurable lesion(s) according to the RECIST 1.1 standard (the CT scan length of the tumor lesion ＞ 10 mm)

7. The main organ function is normal. All baseline laboratory requirements will beassessed and should be obtained within -14 days of randomization. Screening laboratoryvalues must meet the following criteria. a .Hemoglobin ≥ 9.0 g/dL (90 g/L) b .Absoluteneutrophil count ≥ 1.5 x 109/L c .Platelets ≥ 100 x 109/L d .Total bilirubin (TBIL) ≤ 1 x upper limit of normal (ULN) e .Alanine aminotransferase (ALT) and aspartateaminotransferase (AST) ≤ 1.5 x upper limit of normal(ULN); alkaline phosphatase ≤ 5 xULN f .Serum creatinine ≤ 1.5 x ULN or creatinine clearance ＞ 45 mL/minute (usingCockcroft/Gault formula)

8. Emale participants of childbearing potential must have a negative serum pregnancy testwithin -7 days of randomization and must be willing to use very efficient barriermethods of contraception or a barrier method plus a hormonal method starting with thescreening visit through 60 days (about 5 drug half-life + menstrual cycle) after thelast dose of SHR-1210. Male participants with a female partner(s) of child-bearingpotential must be willing to use very efficient barriermethods of contraception fromscreening through 120 days (about 5 drug half-life + sperm depletion cycle) after thelast dose of SHR-1210.

9. Subjects should be voluntarily participate in clinical studies and informed consentshould be signed.

Exclusion Criteria:

1.Imaging (CT or MRI) showed the presence of a central tumor that invades the local largevessels. Or there are obvious pulmonary cavitation or necrotizing tumors. 2. Patients withbrain metastasis or meningeal metastasis.

3.Subjects used immunosuppressive drugs excluding nasal spray and inhaled corticosteroidsor systemic steroids at physiological doses(prednisolone≤10 mg/day or other corticosteroidsof the same pharmacophysiological dose) within 14 days before the first dose.

4.Uncontrollable hypertension (systolic blood pressure ≥140 mmHg or diastolic bloodpressure ≥90 mmHg, despite with the optimal medical treatment.

5.Subjects with grade II or above myocardial ischemia or myocardial infarction and poorlycontrolled arrhythmias (QTc interval > 450 ms for males and QTc interval > 470 ms forfemales). Subjects with grade III-IV cardiac insufficiency or with left ventricularejection fraction (LVEF) less than 50% had myocardial infarction within 6 months beforeadmission according to NYHA criteria.

6.Accompanied by uncontrolled pleural effusion, pericardial effusion, or ascites requiringrepeated drainage.

7.Participants who had any active autoimmune disease or a history of autoimmune disease (such as the following, but not limited to: autoimmune hepatitis, interstitial pneumonia,uveitis, enteritis, hepatitis, pituitary inflammation, vasculitis, nephritis ,Hyperthyroidism, decreased thyroid function).

8.Subjects with childhood asthma has completely resolved, adults can be included withoutany intervention; subjects with bronchodilators for medical intervention can not beincluded .

9.Participants who had abnormal blood coagulation (INR＞1.5 or PT> ULN+4s, and or APTT > 1.5ULN), bleeding tendency or receiving thrombolytic or anticoagulation；Note: under thepremise that the international standardized ratio of prothrombin time (INR) is ≤ 1.5, theuse of low-dose heparin (60,000-12,000u per day for adults) or low-dose aspirin (≤ 100mgper day) is allowed for preventive purposes.

10.Urine routine indicates urinary protein ≥ ++, or confirms that 24-hour urine protein is ≥1.0 g.

11.Patients with non-healing wound, non-healing ulcer, or non-healing bone fracture; 12.Thepatient has severe infection within 4 weeks before first administration（such as the needfor intravenous antibiotics, antifungals or antivirals) and unexplained fever within 7 daysbefore administration, ≥38.5 °.

13.There was significant coughing blood and significant clinically significant bleedingsymptoms or a clear tendency to hemorrhage in the first 2 months before enrollment (such asgastrointestinal bleeding, hemorrhagic gastric ulcer, fecal occult blood ++ and above atbaseline, or suffering from vasculitis, etc.).

14.Serious Arterial / venous thrombosis events, such as cerebrovascular accidents (including transient ischemic attacks, cerebral hemorrhage, cerebral infarction), deep veinthrombosis, and pulmonary embolism, within 12 months before enrollment.

15.Known history of testing positive for human immunodeficiency virus (HIV) or knownacquired immunodeficiency syndrome (AIDS).Positive test for hepatitis B virus surfaceantigen (HBV sAg) or hepatitis C virus ribonucleic acid (HCV RNA) indicating acute orchronic infection. (HBV: HBsAg positive and HBV DNA ≥ 500 IU/mL ; HVC: HCV RNA positive andabnormal liver function). And subjects with active tuberculosis.

16.Patients with a clear history of allergies may be potentially allergic to or intolerantto biological agents such as irinotecan, cisplatin, apatinib, and carillizumab; 17.Thereare obvious factors affecting oral drug absorption, such as inability to swallow, chronicdiarrhea and intestinal obstruction. Or sinus or perforation of empty organs within 6months.

18.Any known mental illness or substance abuse that may have an impact on compliance withthe test requirements.

19.There are other factors lead to patients can not participate in this clinical study bythe judgment of the investigator.