The cost-effectiveness of toripalimab combined with chemotherapy versus chemotherapy alone in the first-line treatment of extensive-stage small cell lung cancer in China: the perspective of the medical and health system based on the EXTENTORCH study.

[OBJECTIVE] To evaluate the cost-effectiveness of toripalimab combined with chemotherapy for the first-line treatment of extensive-stage small cell lung cancer.

[METHODS] A partitioned survival model was employed with data sourced from the EXTENTORCH clinical trial and related literature. The simulation period was set to 10 years, with a cycle of 3 weeks, and all cost and utility indicators were adjusted using a 5% annual discount rate. Using QALYs as the main evaluation indicator, ICERs were calculated to compare the economic differences between treatment with TC group and PC group. The reliability of the research results was verified through single-factor sensitivity analysis and probabilistic sensitivity analysis.

[RESULTS] From the base analysis indicate that the ICER for the TC group relative to the PC group is $3,151 per QALY, which is significantly lower than the WTP set at three times the 2024 per capita GDP of China. Sensitivity analysis shows that the discount rate, incidence of hematotoxicity in TC group, number of treatment cycles and other parameters have the greatest impact on ICER.

[CONCLUSION] At the current willingness-to-pay threshold for Chinese patients, the combination of toripalimab and chemotherapy demonstrates superior cost-effectiveness compared to traditional chemotherapy.