Cancer Drug Wastage and Mitigation Methods: A Systematic Review.

Objectives: To systematically review published evidence on cancer drug wastage and the effectiveness of mitigation methods.

Methods: Search keywords for Scopus, PubMed, and EMBASE were developed using the Pearl Growing technique. Relevant articles were identified in a 2-step process: first, based on titles/abstracts, then on full article reviews. Among the identified English peer-reviewed articles, those considering adults ≥18 years and relevant cancer drug wastage outcomes were included. Key concepts and measures for drug wastage and its mitigation were tabulated. Trends in publication numbers were analyzed using Mann-Kendall tests. Costs were converted first to 2024 local currencies using country-wise consumer price indexes and then to 2024 USD using exchange rates.

Results: Among 6298 unique articles, 94 met the inclusion criteria. Seventy-four (79%) of these were published since 2015, highlighting increasing attention to cancer drug wastage. Twenty-three articles (24%) explicitly reported drug wastage amounts, whereas 52 articles (55%) considered the mitigation methods. Most articles focused on high-income countries (n = 67), single-hospital settings (n = 45), and retrospective study designs (n = 55). Wastage mitigation techniques included vial sharing (n = 21), dose rounding (n = 17), closed-system transfer device (n = 9), centralized drug preparation (n = 7), and vial size optimization (n = 7). A trend toward higher median wastage cost was evident in US settings ($135.35/patient-month) compared with other countries ($37.71/patient-month), whereas mitigation methods across countries were not statistically significant.

Conclusions: High cancer drug costs highlight the importance of minimizing drug wastage to reduce healthcare expenditure. Our review demonstrates that wastage varies by healthcare setting and mitigation technique. Future studies would benefit from reporting standards for cancer drug wastage that include reporting wastage (both in mg and cost, preferably in terms of purchase power parity), as well as cohort size, considered vial sizes, considered dosages, and used mitigation methods separately for each drug. This approach would account for variability in cancer drug wastage and help identify optimal mitigation practices tailored to the health system context.