CC4 COST-EFFECTIVENESS ANALYSIS OF PERTUZUMAB WITH TRASTUZUMAB AND CHEMOTHERAPY COMPARED TO TRASTUZUMAB AND CHEMOTHERAPY IN THE ADJUVANT TREATMENT FOR PATIENTS WITH HER2-POSITIVE EARLY BREAST CANCER AT HIGH RISK OF RECURRENCE IN CHINA

To estimate the cost-effectiveness of pertuzumab with trastuzumab and chemotherapy (PHT) vs trastuzumab and chemotherapy (HT) as the adjuvant treatment for Chinese patients with HER2-positive early breast cancer at high risk of recurrence (HR-negative or node-positive). A 6-state Markov model with monthly cycle was constructed to estimate the lifetime incremental cost-effectiveness ratio (ICER). Main clinical input was the time spent in invasive Disease Free Survival state, estimated by parametric extrapolations to the Chinese subgroup data observed in the clinical trial APHINITY. Utilities were calculated from EQ-5D of Chinese patients in APHINITY with Chinese Tariffs and the published literatures. The modelled adjuvant cost comprised drugs, administration, adverse events management costs, follow-up and therapeutic cost. Furthermore, indirect costs were included when analyzed from the society perspective. All costs were mainly obtained from real world data and local published resources. Costs and outcomes were both discounted at 5%. Sensitivity analysis were conducted to verify the robustness of the results. PHT provided 1.02 more QALYs with additional costs than HT. From healthcare system perspective, the ICER was CNY 115,329/QALY. Further 26% lower indirect costs in PHT group resulting an ICER of CNY 107,400/QALY from the society perspective. Both ICERs were between 1∼2 times GDP per capita, far below the local threshold of 3 times GDP per capita in 2018 (CNY 193,932). Acquisition cost of pertuzumab is partially offset by the prevention of disease recurrences over the time. Cost for managing recurrences in PHT was 42% lower than that in HT group. Probabilistic sensitivity analysis showed that PHT was more cost-effective in more than 70% simulations at local threshold regardless of the perspective. Compared to HT, PHT is more cost-effective in the adjuvant treatment for patients with HER2-positive early breast cancer at high risk of recurrence in China.