Reuse of fixed-dose monoclonal antibodies in oncology: retrospective and pharmacoeconomic analysis in a chemotherapy reconstitution unit

OBJECTIVE: To evaluate the efficiency, safety and economic impact of reattributing fixed-dose monoclonal antibody preparations in a chemotherapy reconstitution unit to reduce waste associated with anticipated preparation. METHODS: A retrospective, single-centre study was conducted over the period from April 2023 to April 2025, including 7524 fixed dose monoclonal antibody preparations. Primary outcomes were the rate of reuse versus destruction, temporal trends, molecular factors influencing reuse and direct cost savings. Safety was ensured via Chimio 6.0 traceability and validation by the hospital pharmacist. RESULTS: Of 7524 preparations, 290 (3.85%) were non-administered. Among these, 265 bags were successfully reattributed, corresponding to a 91.4% success rate and an overall reuse rate of 3.52%, with a significant increase over time (from 2.5% in 2023 to 4.6% in early 2025; p<0.001). Reuse avoided €1.19 million in drug expenditure, whereas 25 destroyed preparations (€113 381) were mainly lost due to cold chain breach. CONCLUSION: Reuse of fixed dose monoclonal antibody preparations in a chemotherapy reconstitution unit is safe, effective and economically impactful, providing a strategic tool for oncology pharmacy management.