Cost-effectiveness analysis of regorafenib dose optimization for refractory metastatic colorectal cancer

New regimens have emerged as third-line or later therapies for metastatic colorectal cancer (mCRC), including regorafenib dose optimization (ReDO), trifluridine/tipiracil and bevacizumab (TAS-BEV) combination therapy, and fruquintinib. We evaluated relative cost-effectiveness of these therapies in patients with mCRC from a US payer's perspective.

A partitioned survival model (PSM) was constructed to estimate total costs and quality-adjusted life years (QALYs). Clinical parameters were obtained from pivotal trials of the respective therapies and incremental cost-effectiveness ratios (ICERs) were estimated to assess relative cost-effectiveness of these treatments. Model robustness was assessed using deterministic (DSA) and probabilistic sensitivity analysis (PSA). Three scenario analyses were conducted: (1) assuming equal efficacy across treatments, (2) with prior exposure to anti-vascular endothelial growth factor (VEGF) therapy, and (3) alternative clinical inputs for fruquintinib from a different clinical trial.

Under the conventional willingness-to-pay (WTP) threshold in US ($150,000 per QALY gained), ReDO was cost-effective when compared with TAS-BEV and was dominant over fruquintinib. TAS-BEV was associated with an incremental QALY of 0.197 over ReDO, resulting in an ICER at $554,567 per QALY gained. The base case results were robust in DSA and PSA. Most influential parameters were treatment cost and effectiveness. In patients with prior anti-VEGF therapy, ReDO remained cost-effective compared to TAS-BEV and fruquintinib under the conventional WTP threshold.

Differences in trial populations may affect the comparability of the outcomes. Sensitivity and scenario analyses were conducted to address these limitations.

ReDO was cost-effective compared with TAS-BEV from the US payer's perspective despite a higher QALY gain associated with TAS-BEV. ReDO was dominant over fruquintinib, consistently having a higher QALY gain and lower cost.