Cost-effectiveness of sugemalimab plus chemotherapy versus placebo plus chemotherapy as first-line treatment for advanced oesophageal squamous cell carcinoma in China.

Abstract

Sugemalimab plus chemotherapy significantly prolonged progression-free survival and overall survival in patients with advanced oesophageal squamous-cell carcinoma (ESCC). However, considering the high cost of sugemalimab, we evaluated the cost-effectiveness of sugemalimab plus chemotherapy in the first-line treatment for advanced ESCC. A partitioned survival model with a 3-week cycle length and the lifetime time horizon was constructed to assess the cost-effectiveness of sugemalimab plus chemotherapy versus placebo plus chemotherapy as first-line treatment for advanced ESCC. The key survival data, drug costs, and utility values were obtained from the GEMSTONE-304 trial, YAOZHI database and the published literature. Total costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) were measured. One-way and probabilistic sensitivity analyses were performed to evaluate the uncertainty and model stability. In addition, subgroup and scenario analyses were conducted. The Chinese healthcare system perspective. A hypothetical Chinese cohort of patients with unresectable, locally advanced, recurrent or metastatic ESCC. Sugemalimab plus chemotherapy versus chemotherapy. Costs, QALYs, ICERs. Compared with the placebo plus chemotherapy, the sugemalimab plus chemotherapy provided an additional 0.36 QALYs, with an incremental cost of $44 376.88. The result of ICER was $119 400.69/QALY, which was significantly higher than the willingness-to-pay (WTP) threshold of three times per capita gross domestic product ($38 024.68/QALY) in 2023. Sensitivity analysis revealed that the cost of sugemalimab, the discount rate and the utility values were the most influential parameters on the base-case analysis results. Subgroup analyses showed that programmed cell death - ligand 1 subgroup ICERs exhibited dose-dependent efficacy: the ICERs for sugemalimab plus chemotherapy versus placebo plus chemotherapy were $138 739.23/QALY and $108 051.81/QALY in advanced ESCC patients with 1 ≤ combined positive score (CPS) <10 and CPS ≥10. Scenario analysis indicated that even with patient assistance programme, the total cost of the sugemalimab plus chemotherapy group ($23 474.25) would be $15 030.18 higher than that of the placebo plus chemotherapy group ($8444.07), which had an ICER of $40 440.28/QALY. When the price of sugemalimab decreased by 50% and 85%, the probabilities of sugemalimab plus chemotherapy being cost-effective were 0% and 100%, respectively. From a Chinese healthcare system perspective, sugemalimab plus chemotherapy as first-line treatment for advanced ESCC might not be a cost-effective treatment option at the WTP threshold of $38 024.68/QALY.