Cost-effectiveness analysis of serplulimab combined with chemotherapy in the treatment of extensive-stage small-cell lung cancer from the perspective of the healthcare system in China

OBJECTIVE: The ASTRUM-005 trial showed that serplulimab plus chemotherapy (SEP) significantly extended survival time compared with chemotherapy in the treatment of small cell lung cancer. But the survival benefits of SEP came at high costs, and its economy is not clear. Therefore, this study aimed to evaluate the cost-effectiveness of SEP from the perspective of the Chinese healthcare system. DESIGN: A partition survival model was built to simulate the outcomes. The clinical data came from the ASTRUM-005 trial, and only direct medical costs were included in the model. The utility values referred to the published literature. Scenario analyses 1 and 2 explored outcomes in the presence of a patient assistance plan (PAP) and different simulation periods, respectively. Scenario analysis 3 compared the cost-effectiveness of atezolizumab plus chemotherapy (AEP) with SEP by network meta-analysis. Sensitivity analyses were conducted to assess the robustness of the results. OUTCOME MEASURES: Total costs, incremental costs, life years, quality-adjusted life years (QALYs), incremental QALYs and incremental cost-effectiveness ratio (ICER). RESULTS: Compared with chemotherapy, SEP achieved an additional 0.34 QALYs at incremental costs of US$41 682.63, with an ICER of US$122 378.86/QALY. When PAP was available, ICER was US$58 316.46/QALY. In the simulation time of 5 years and 20 years, the ICER was US$132 637.97/QALY and US$118 054.59/QALY, respectively. When compared with AEP, SEP not only reduced the costs by US$47 244.87 but also gained 0.07 QALYs more. Sensitivity analyses showed that the price of serplulimab and the utility value of the progression-free survival stage were the main influencing parameters, and the results were stable. CONCLUSIONS: Compared with chemotherapy, SEP was not cost-effective from the perspective of the Chinese healthcare system. However, SEP was absolutely dominant in comparison with AEP.