目的 一项随机、多中心、开放标签、III期试验（IMforte）显示，芦比替定（Lurbinectedin）联合阿替利珠单抗（Atezolizumab）一线治疗广泛期小细胞肺癌（ES-SCLC），与单用阿替利珠单抗相比，可显著延长总生存期和无进展生存期。本研究旨在从美国的角度评估芦比替定联合阿替利珠单抗作为广泛期小细胞肺癌患者一线治疗的成本-效益。方法 基于IMforte试验，开发了一个马尔可夫（Markov）模型来模拟广泛期小细胞肺癌的发展过程，包括三种健康状态：无进展生存期（PFS）、疾病进展期（PD）和死亡。模型模拟时间范围为10年，周期为3周。研究以成本和生命质量调整年（QALYs）作为模型的产出指标，通过成本-效益分析计算增量成本-效益比（ICER），评估芦比替定联合阿替利珠单抗相较于单用阿替利珠单抗的经济可行性。采用敏感性分析和情境分析检验模型的稳健性。结果 与单独使用阿替利珠单抗相比，芦比替定联合阿替利珠单抗组成本增加85854.15美元，增量效益值为0.2 QALYs。与阿替利珠单抗组相比，芦比替定联合阿替利珠单抗组不具有成本效益，增量成本效益比（ICER）为429270.75美元/QALY，超过了150000美元的支付意愿阈值。该模型对芦比替定联合阿替利珠单抗组成本和PFS效用值最敏感。结论 从美国支付者角度来看，芦比替定联合阿替利珠单抗不是广泛期SCLC一线治疗的成本效益选择。

Objective A randomized, multicenter, open-label, phase III trial (IMforte) demonstrated that lurbinectedin combined with atezolizumab significantly prolonged overall survival and progression-free survival in patients with extensive-stage small cell lung cancer (ES-SCLC) compared with atezolizumab alone. This study aimed to evaluate the cost-effectiveness of lurbinectedin combined with atezolizumab as first-line treatment for ES-SCLC from the perspective of the United States. Methods Based on the IMforte trial, a Markov model was developed to simulate the disease progression of ES-SCLC, including three health states: progression-free survival (PFS), disease progression (PD), and death. The model simulation period was 10 years with a 3-week cycle. The model used cost and quality-adjusted life years (QALYs) as output indicators, and the incremental cost-effectiveness ratio (ICER) was calculated through cost-effectiveness analysis to assess the economic feasibility of lurbinectedin combined with atezolizumab compared with atezolizumab alone. Sensitivity analysis and scenario analysis were conducted to test the robustness of the model. Results Compared with atezolizumab alone, the lurbinectedin combined with atezolizumab group had an additional cost of $85,854.15 and an incremental benefit of 0.2 QALYs. The lurbinectedin combined with atezolizumab group was not cost-effective compared with the atezolizumab group, with an ICER of $429,270.75/QALY, exceeding the willingness-to-pay threshold of $150,000. The model was most sensitive to the cost and PFS utility value of the lurbinectedin combined with atezolizumab group. Conclusion From the perspective of US payers, lurbinectedin combined with atezolizumab is not a cost-effective option for first-line treatment of ES-SCLC.