Efficacy and Safety of Serplulimab With Chemotherapy and Aspirin in Untreated Extensive-Stage Small Cell Lung Cancer

Participants will receive an induction therapy consisting of Serplulimab (4.5 mg/kg IV on Day 1), Carboplatin (AUC 5 IV on Day 1) or Cisplatin (75 mg/m² IV on Day 1), Etoposide (100 mg/m² IV on Days 1-3), and Bayer Aspirin (100 mg PO daily). This induction phase will be administered every 3 weeks for 4 cycles. Following the induction phase, participants will transition to a maintenance therapy phase where they will continue to receive Serplulimab (4.5 mg/kg IV on Day 1, every 3 weeks) and Bayer Aspirin (100 mg PO daily) until disease progression or intolerable toxicity.