Cost-Effectiveness Analysis of SOX Plus Bevacizumab Versus SOX Plus Cetuximab for First-Line Treatment of KRAS Wild-Type Metastatic Colorectal Cancer in Japan.

Objective: In this study, we aimed to evaluate the cost-effectiveness of S-1 and oxaliplatin (SOX) plus bevacizumab (Bmab group) compared with SOX plus cetuximab (Cmab group) as a first-line treatment for patients with Kirsten rat sarcoma virus (KRAS) wild-type metastatic colorectal cancer (mCRC) in Japan from the perspective of healthcare payers.

Methods: A partitioned survival model was developed using data from the randomized phase II Osaka Multicenter Study Group on Colorectal Cancer-1107 study, which included overall survival, progression-free survival, and treatment regimens for the Bmab and Cmab groups. Treatment costs were estimated from the Japanese medical claims database and the National Health Insurance drug price list. The utilities were derived from the literature. Outcomes were reported as incremental cost, incremental quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). The willingness-to-pay (WTP) threshold was set at 7.5 million JPY per QALY. The time horizon of the model was set to 20 years. Sensitivity analyses were conducted to assess the uncertainty of the model for various parameters.

Results: Compared with the Cmab group, the Bmab group had an incremental cost of 911,373 JPY (6,528 USD), an incremental effectiveness of 0.79 QALY, and an ICER of 1,146,745 JPY (8,215 USD) per QALY. One-way sensitivity analysis showed that the cost of progressive disease treatment in the Bmab group had the greatest impact on the ICER. According to the probabilistic sensitivity analysis, the Bmab group had a 94.9% probability of being cost-effective compared with the Cmab group.

Conclusions: Considering a WTP threshold of 7.5 million JPY (approximately 53,700 USD) per QALY, Bmab might be a cost-effective treatment option for patients with KRAS wild-type mCRC in Japan. Further studies on economic evaluations based on personalized drugs and patient selection based on clinical and genetic information are warranted.