Effects of Carton Redesign following Package Insert Digitization on Usability and Carbon Footprint of Vaccine Vials

We evaluated the impact of changes in carton specifications for two-vial, human-use vaccine products on usability and carbon footprint. The modifications were implemented to enhance functionality and usability following the digitization and elimination of package inserts. Although sensory evaluations conducted among healthcare professionals involved in vaccination exhibited substantial individual variation, ratings for carton openability, resealability, vial removability, and vial holding position improved after the changes when comparing mode scores. By contrast, ratings for cushioning and disposability were higher before the changes, indicating areas for further improvement. Following the specification changes, the carton became heavier because of the increased surface area required for cushioning, resulting in a higher carbon footprint for the carton alone. However, when the reduction in package insert usage was considered, the overall carbon footprint decreased. Furthermore, the number of vial breakage reports from the market introduction of the revised products through the end of fiscal year 2025 declined substantially compared with the pre-change period, confirming the feasibility and safety of real-world implementation.