Cost-utility Analysis of Ribociclib Combined with Letrozole as First-line Treatment for HR+/HER2− Advanced or Metastatic Breast Cancer

OBJECTIVE  To evaluate the cost-effectiveness of ribociclib in combination with letrozole as a first-line treatment for HR+/HER2− advanced or metastatic breast cancer from the perspective of the Chinese healthcare system.

METHODS The partitioned survival model was constructed using the survival data of MONALEESA-2 clinical trial, along with relevant cost and utility data. The model cycle was set at 4 weeks, with a simulation time horizon of 20 years, and a discount rate of 5%. The output measures of the model were cost and quality adjusted life years(QALYs), and the evaluation metric was the incremental cost-effectiveness ratio(ICER). The willingness-to-pay(WTP) threshold was set at three times China’s per capita GDP in 2023( ¥268074·QALY⁻¹). The robustness of the model was assessed through one-way sensitivity analysis and probabilistic sensitivity analysis, and scenario analyses were also conducted.

RESULTS The base case analysis results indicated that ribociclib combined with letrozole provided greater health benefits compared to letrozole monotherapy, but it also incurred higher total costs. The incremental utility and incremental cost were 0.81 QALYs and ¥186527.76, respectively, resulting in an ICER of ¥230994.70·QALY⁻¹ for the comparison between the two regimens. One-way sensitivity analysis, probabilistic sensitivity analysis, and scenario analysis confirmed the robustness of the model results. The scenario analysis results showed that as the simulation time horizon extended, the ICER value of ribociclib combined with letrozole gradually decreased, with the rate of decline tending to diminish. Long-term treatment regimens exceeding 15 years demonstrated higher cost-effectiveness.

CONCLUSION From the perspective of the Chinese healthcare system, ribociclib in combination with letrozole as a first-line treatment for postmenopausal patients with HR+/HER2− advanced or metastatic breast cancer has high cost-effectiveness. Additionally, the treatment shows stronger economic viability over longer time horizons.