Pharmacoeconomic Analysis of Carrelizumab in NSCLC

The study only considered direct medical costs, including drug acquisition, follow-up, best supportive treatment, and severe adverse event (SAE) management costs. In accordance with the ESCORT clinical research and guidelines (CSCO, 2020 ; Huang et al., 2020 (link)), 200 mg carrelizumab was administered intravenously on the first day of every 2 weeks, 75 mg/m² docetaxel was provided on the first day of every 3 weeks, and 180 mg/m² of irinotecan was administered intravenously on the first day every 2 weeks. Treatment was continued until disease progression or unacceptable toxicity. The cost effectiveness of the two scenarios was discussed to avoid the effect of the course of drugs on the results. In the first scenario, camrelizumab was assumed to be used for six (IQR 4–13) courses, docetaxel for three (2–3) courses, and irinotecan for four (2–5) courses in accordance with the results of ESCORT (Huang et al., 2020 (link)). A shorter time horizon (3, 5 and 7 years) was also considered in this scenario. In the second scenario, both groups continued treatment until the disease progressed. The proportion of patients receiving specific chemotherapy regimens was not defined in the clinical trials. The model assumed that the patients had equal opportunities to receive docetaxel and irinotecan. The average body surface area of the patients in the model was 1.72 m² (1.5–1.9 m²) (Zeng et al., 2013 (link)). After the failure of second-line treatment, the best third-line treatment was not clear, and the specific scheme was not shown in the ESCORT study. Therefore, the best support treatment was regarded as the treatment after progression.
The cost of camrelizumab was derived from the negotiated price of China’s national medical insurance (Nation Healthcare Security Administration, 2020 ). The cost of docetaxel and irinotecan was the median of the bidding price of drugs in different provinces (YaoZH, 2020 ). Only the SAE of grade ≥3 was considered (Guy et al., 2019 (link); Zhang et al., 2020b (link)). The incidence rate of anemia in the camrelizumab group was 3%, while the incidence rates of anemia, decreased neutrophil count, and vomiting in the chemotherapy group were 5.0, 15.0, and 5%, respectively (Huang et al., 2020 (link)). Other costs are shown in Table 1.
The utility value represents the health-related quality of life for each health state. The ESCORT trail did not involve health utility. Thus, the utility in the model was obtained from other public literature (Tan et al., 2018 (link); Zhang et al., 2020b (link); National Institute for Health and Care Excellence, 2021 ), utility values for the PFD and PD health states were taken from EQ-5D data from a global, randomised, placebo-controlled, double-blind, phase 3 study, which recruited adults with advanced gastric cancer or gastro–oesophageal junction adenocarcinoma. The utility of PFD in the two groups was assumed to be consistent, but SAE (grade ≥3) could affect the utility. After disease progression, the utility of all patients in PD state was 0.581 (Zhang et al., 2020b (link); National Institute for Health and Care Excellence, 2021 ). All utility values are shown in Table 1.