Abstract
BACKGROUND: This study aimed to assess the cost-effectiveness of capecitabine versus active monitoring in stable or responding metastatic colorectal cancer (mCRC) after 16 weeks of first-line therapy. METHODS: A partitioned survival model (PSM) was constructed to determine the costs and effects of capecitabine and active monitoring based on FOCUS4-N trial data. The Chinese healthcare payer's perspective was considered with a lifetime horizon, including direct medical costs. Health outcomes were measured in quality-adjusted life years (QALYs). The cost-effectiveness was assessed by calculating the incremental cost-effectiveness ratio (ICER). A willing-to-pay (WTP) threshold was set at 37653 USD/QALY, which was three times the gross domestic product (GDP) per capita of China in 2021. We examined the robustness of the model in one-way and probabilistic sensitivity analysis (PSA). RESULTS: There was no significant difference between capecitabine arm and active monitoring arm in QALYs (0.93 vs 0.92). The total cost of capecitabine arm was higher than that of active monitoring (35 061.61 USD vs 13 677.18 USD), suggesting the capecitabine group was not cost-effective in stable or responding mCRC after 16 weeks of first-line therapy. The cost of capecitabine and active monitoring had the largest impact on the ICER through one-way sensitivity analysis. The PSA indicated a 100% probability that active monitoring arm was cost-effective under the WTP. CONCLUSIONS: Compared to active monitoring, maintenance treatment with capecitabine alone was not cost-effective in stable or responding mCRC after 16 weeks of first-line therapy.