OBJECTIVE  To analyze the cost-effectiveness of pembrolizumab combined with basal chemotherapy for the first-line treatment of advanced steno-negative breast cancer(TNBC) with PD-L1 combined positive score≥10.

METHODS  Based on the KEYNOTE-355 clinical trial data, a partitioned survival model was constructed to evaluate the economics of pabolizumab. Survival functions were fitted based on progression-free survival(PFS) curves and overall survival curves from the KEYNOTE-355 trial. Cost data were obtained from Beijing Friendship Hospital, Capital Medical University, utility data and cost and incidence rates related to adverse reactions were obtained from the literature, and sensitivity analyses were performed on the parameters.

RESULTS  The results of the base analysis showed that the incremental cost-effectiveness ratio of the pembrolizumab combined with chemotherapy group was ¥1187081.46/QALY compared to placebo combined with chemotherapy group. Uncertainty analyses showed that the price of pabolizumab and the utility value of PFS had a large impact on the variability of the results, with pabolizumab having the largest impact.

CONCLUSION  Under the willingness-to-pay thresholds of 3 times the per capita GDP in China(¥257094) and 3 times the per capita GDP in Beijing(¥570 000), pabolizumab don’t have a cost effect, and its affordability can be increased by lowering the price of pabolizumab.