To Evaluate Efficacy and Safety of Serplulimab + Chemotherapy (Carboplatin- Etoposide) in US Patients With ES-SCLC

Other illness

• Known history of severe allergy to any monoclonal antibody.
• Known hypersensitivity to carboplatin or etoposide.
• Patients with myocardial infarction within half a year before the first dose of the study drug, poorly controlled arrhythmia.
• Patients with a known history of psychotropic drug abuse or drug addiction.

Other

• Histologically or cytologically confirmed mixed SCLC.
• Pregnant or breastfeeding females.
• Patients who have other factors that could lead to the early termination of this study based on the investigator's judgment.

• Voluntary participation in clinical studies.
• Male or female aged ≥ 18 years at the time of signing the ICF.
• Histologically or cytologically diagnosed with ES-SCLC (according to the Veterans Administration Lung Study Group staging system).
• No prior systemic therapy for ES-SCLC.
• At least one measurable lesion as assessed according to RECIST 1.1 within 4 weeks prior to randomization.
• Major organs are functioning well.
• Every effort should be made to provide tumor tissues for the determination of PD-L1 expression.
• An ECOG PS score of 0 or 1.
• An expected survival ≥ 12 weeks.
• Subjects with prior denosumab use that can and agree to switch to bisphosphonate therapy for bone metastases starting prior to randomization and throughout treatment.
• Participant must keep contraception.