Abstract
BACKGROUND: The NCT04878016 trial evaluated the efficacy and safety of socazolimab in combination with carboplatin/etoposide as a first-line treatment for extensive-stage small cell lung cancer (ES-SCLC). This study aims to analyze the cost-effectiveness of this combination regimen from the perspective of the Chinese healthcare system. METHOD: A Markov model with three health states was constructed. The model simulated a time horizon of 10 years with a cycle length of 3 weeks. Costs and utilities were discounted at 5% annually. The primary outcomes were total costs, quality-adjusted life years (QALYs), and the incremental cost-effectiveness ratio (ICER). One-way sensitivity analysis and probabilistic sensitivity analysis were conducted to assess the robustness of the results. RESULTS: The base-case analysis showed that the ICER for the socazolimab group compared to the chemotherapy-alone group was 355,316.95 yuan/QALY, which exceeds three times China's per capita GDP in 2024 as the willingness-to-pay (WTP) threshold. One-way sensitivity analysis revealed that PD utility, PFS utility, socazolimab cost, and neutropenia management cost had significant impacts on model results. Probabilistic sensitivity analysis indicated that the probability of socazolimab combined with chemotherapy being cost-effective was 21.9%. CONCLUSION: At China's WTP threshold, socazolimab combined with chemotherapy is not cost-effective versus chemotherapy alone for ES-SCLC.