ESCC is one of the most prevalent malignancies worldwide. Despite the widespread use of chemotherapy as first-line treatment, the treatment options for advanced ESCC remain limited, and the prognosis is poor. In recent years, the advent of ICIs has provided new treatment options for advanced ESCC[10, 30]. The ORIENT-15 trial showed that sintilimab plus chemotherapy significantly prolonged the median PFS and median OS in patients with advanced ESCC, providing a new first-line treatment option for ESCC patients.
To our knowledge, this was the first study to estimate the cost-effectiveness of a sintilimab combination strategy for the first-line treatment of patients with advanced ESCC in China. The results illustrated that the ICERs of the sintilimab combination strategy were $14,967.31/QALY and $-20,244.80/QALY in the overall and PD-L1-positive populations, respectively. One-way sensitivity analysis showed that health state utility values were the most influential factor in the model. A possible explanation was that the health state utility values of PFS and PD were obtained from published literature and not from Chinese ESCC patient data. PSA confirmed the robustness of the base-case analysis results.
Currently, there is no cost-effectiveness analysis associated with sintilimab for advanced ESCC. However, cost-effectiveness analyses[22–24, 27, 31]of nivolumab and pembrolizumab have been reported using data from several clinical trials, including Checkmate-648, ATTRACTION-3, Checkmate-649, KEYNOTE-181, and KEYNOTE-590. Due to the high price, studies have found that nivolumab or pembrolizumab are not cost-effective options for advanced ESCC in either first- or second-line treatment. For pembrolizumab, the results of the two studies[31, 32]based on the KEYNOTE-181 trial were inconsistent, possibly due to the different cost measurements, modelling techniques, total costs, and QALYs used in the two studies.
Several potential limitations must be discussed in this study. First, we used data from the ORIENT-15 trial to reconstruct individual patient data, as the original data were not available from the published literature. Although this approach introduces some bias to this study, it maximally reflected the actual survival data as observed in clinical trials. Second, the cost and utility of grade 1–2 adverse events were not considered in this study, which may reduce the credibility of the results, but the results of the one-way sensitivity analysis showed that the model results were not sensitive to parameters related to adverse events. Third, the utilities of different health states were obtained from the published literature. Utility based on Chinese advanced ESCC is still lacking. Therefore, we performed sensitivity analysis to estimate the effect of changes in utility values on the results. Fourth, the current study failed to compare the cost-effectiveness of sintilimab with other treatment strategies because of the lack of head-to-head clinical trials. Despite these limitations, we believe that this analysis accurately reflected the clinical situations of advanced ESCC in China, and our results may provide valuable information for Chinese policymakers.