Comparison of dose rounding and drug vial optimization for reducing anticancer drug waste.

Introduction: Numerous injectable anticancer drugs are administered at varying doses based on the body surface area and weight of the patients, often resulting in a certain volume of residual medication. Several anticancer drugs are expensive, thus, their increased use has led to a corresponding increase in drug waste and healthcare costs. Two potential solutions to this issue include drug vial optimization (DVO) and dose rounding (DR). However, DR has rarely been implemented in Japan. Here, we evaluated DVO and DR to assess whether DR could be a viable strategy to reduce the number of anticancer drugs discarded and minimize drug-related costs in Japan. Methods: Patients who received bevacizumab, ramucirumab, gemcitabine, or levofolinate between January and December 2023 at Kanagawa Prefectural Ashigarakami Hospital (Ashigarakami) and Ogaki Municipal Hospital (Ogaki) were included in this study. Actual quantities used for each anticancer drug were extracted from electronic medical records, and the quantities used of drugs during the application of DVO and DR were calculated. Based on these findings, we estimated the reduction in drug waste and the associated cost savings for DVO and DR. Results: DR was more effective than DVO in minimizing the waste of drugs, with 0% waste for gemcitabine at Ogaki and 0% waste for levofolinate at both institutions. Conclusion: Compared with DVO, DR is not influenced by the number of patients treated or the volume of anticancer drugs administered, making it feasible for implementation across a wide range of institutions and a highly effective strategy for minimizing waste. DR should be advocated as a key approach for reducing drug costs in Japan in the future.