Cost-Effectiveness Analysis of Neoadjuvant Chemotherapy with Zoledronic Acid for HER2-Negative Breast Cancer in Japan: The JONIE1 Study

Objective: Zoledronic acid (ZOL) is a nitrogen-containing bisphosphonate that induces osteoclast apoptosis and inhibits bone resorption. Adding ZOL to neoadjuvant chemotherapy has been shown to have potential anticancer benefits in women with HER2-negative breast cancer. The objective of the present study was to investigate ZOL’s cost-effectiveness from the perspective of health care payers in Japan. Methods: A Markov model was developed to evaluate the costs and effectiveness associated with ZOL + chemotherapy (CTZ) and chemotherapy (CT) alone over a 10-year time horizon. Monthly transition probabilities were estimated according to JONIE1 (Japan Organization of Neoadjuvant Innovative Expert) Study data and an extrapolated Weibull model. Health outcomes were measured in quality-adjusted life years (QALYs). Costs were calculated using year-2018 Japanese yen (JPY) (1.00 US dollars (USD) = 110.4 JPY). Model robustness was addressed through one-way and probabilistic sensitivity analysis. The costs and QALYs were discounted at a rate of 2% per year. Results: In the base case, the use of CTZ was associated with a gain of 3.94 QALYs. The incremental cost per QALY of the CTZ gain was 681,056.1 JPY (6168.99 USD) per QALY. Conclusion: It is convincing that neoadjuvant CTZ for patients with breast cancer would be expected to have statistically significant clinical efficacy. Addition of ZOL to CT might be a cost-effective option compared with CT alone.