Cost-effectiveness of multigene sequencing test and treatment for metastatic non-small cell lung cancer: A unique setting in the initial adoption phase in Japan allowing testing only after standard treatment.

Objective: To clarify the cost-effectiveness of comprehensive diagnosis and treatment of metastatic non-small cell lung cancer in Japan, from initial diagnosis to post-standard treatment, using three different strategies. Methods: A decision tree was created using three diagnostic and treatment strategies, assuming that Foundation One CDx (F1CDx), a comprehensive genome panel, was introduced in Japan in June 2019. This comprehensive decision tree includes Markov models, cost-effectiveness analyses (CEA), and cost-utility analyses (CUA) of the three strategies from the perspective of Japanese payers. Specifically, Strategy1 involves single-gene testing at the initial diagnosis and F1CDx after standard treatment; Strategy2 involves only single-gene testing at the initial diagnosis; Strategy3 involves F1CDx at the initial diagnosis. The incremental cost-effectiveness ratios (ICERs) of the three strategies are estimated. Sensitivity analyses were performed to assess the uncertainty of the parameter settings. Results: Strategy3 was dominated for both CUA and CEA. The ICER/quality-adjusted life year (QALY) for Strategy2 versus Strategy1 was USD 13,734 (JPY 2,080,923, USD 1 = JPY 151.39 on April 1st, 2024), which is less than the willingness to pay of USD 45,900 (JPY 7,500,000), and Strategy2 was more cost-effective than Strategy1. F1CDx was not cost-effective compared to multiple simultaneous single tests at the initial diagnosis, either after standard treatment or at the initial diagnosis. Sensitivity analysis also showed that the most influential factor on the ICER for both CEA and CUA was treatment cost. Conclusions: From both patient benefit and health economic perspectives, introducing F1CDx after standard treatment in June 2019 was not as cost-effective as multiple simultaneous single tests at the initial diagnosis but was more realistic from a health economic perspective than introducing F1CDx at the time of initial diagnosis. Therefore, the policy at the time of F1CDx introduction in Japan was appropriate from a short-term health-economic perspective.