Comparative Cost-utility Analysis of Regorafenib and Trifluridine/Tipiracil in The Treatment of Metastatic Colorectal Cancer in Japan.

PURPOSE

This study evaluated the cost utility of regorafenib and trifluridine/tipiracil (T/T) compared with that of best supportive care (BSC) in the treatment of patients with metastatic colorectal cancer previously treated with, or not considered candidates for, available therapies, including fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapies; anti-vascular endothelial growth factor agents; and anti-epidermal growth factor receptor agents, in Japan.

METHODS

Efficacy data, utility values, and costs were extracted from published studies. The cost and effectiveness of regorafenib and of T/T were compared with those of BSC and examined between the 2 agents over a 5-year time horizon using a partitioned survival analysis. The health outcomes were life-years (LYs) and quality-adjusted life-years (QALYs) gained. The costs were year-2018 revisions to the drug prices and medical fees. The uncertainty and robustness of the model were verified by 1-way sensitivity analysis, probability sensitivity analysis, and scenario analysis compared with different clinical studies. A 2% per-annum discount was applied to expenses and QALYs. The willingness-to-pay threshold used was 5 million Japanese yen (JPY).

FINDINGS

Regorafenib and T/T had incremental costs of 11,898,982 JPY (107,781 US dollars [USD]) and 5,000,141 JPY (45,291 USD), incremental effects of 0.249 QALYs (0.280 LYs) and 0.344 QALYs (0.421 LYs), and incremental cost-effectiveness ratios of 47,773,791 JPY (432,734 USD) and 14,550,577 JPY (131,799 USD) per QALY, respectively. Results of sensitivity analyses all exceeded the willingness-to-pay threshold of 15 million JPY. In the comparison of the 2 agents, T/T was a dominant alternative over regorafenib.

IMPLICATIONS

As a third-line or later treatment of metastatic colorectal cancer in Japan, T/T is cost-effective compared with BSC, whereas regorafenib is not. It is necessary to adjust the price of regorafenib based on the results of this analysis, with the improvement of clinical parameters such as survival time and adverse events.