Trastuzumab deruxtecan versus chemotherapy treated in patients with HER2-positive metastatic breast cancer: a cost-effectiveness analysis based on the DESTINY-Breast02 trial

This study aims to conduct a cost-effectiveness analysis of trastuzumab deruxtecan versus chemotherapy for HER2-positive metastatic breast cancer from the perspective of the Chinese healthcare system. A three-state partitioned survival model was constructed to simulate the treatment. The analysis yielded information on the costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). Sensitivity analyses have been carried out to scrutinize the model’s uncertainties The total cost for the trastuzumab deruxtecan group was found to be $228601.57, while the chemotherapy group incurred a total cost of $84901.38. It was found that the trastuzumab deruxtecan group exhibited an incremental gain of 2.95 QALYs in comparison to the chemotherapy group. However, this additional benefit came at an additional cost of $143700.19 for the trastuzumab deruxtecan treatment, calculated in the ICER at $48711.93/QALY, which surpasses the willingness-to-pay threshold of $37304.34/QALY in China. Sensitivity analyses indicated that the results were robust to variations in key parameters and assumptions. Trastuzumab deruxtecan was not a cost-effective treatment option for patients with HER2-positive metastatic breast cancer in China. However, the use of trastuzumab deruxtecan may offer a cost-effective treatment alternative provided that its price is diminished.