A research team in Japan recently found that a substantial amount of drug wastage occurs with bodyweight-based dosing of nivolumab, and they reported their findings in the journal JCO Oncology Practice.
Samples for this study were collected from 17 hospitals within Hokkaido, Japan. In Japan, the dosing regimen of nivolumab shifted from being based on bodyweight to becoming a fixed amount of 240 mg per dose. During the 6 months prior to this change, the researchers had acquired vials of nivolumab that had been discarded after preparation. The researchers tested the remaining contents for stability, which was based on both immunoglobulin G (IgG) concentration and binding activity to programmed death-1 (PD-1) protein.
The researchers tested 2789 vials of 100-mg size and 4069 vials of 20-mg size. The total cost of nivolumab associated with these vials was $12.1 million. They calculated that there was a 6.1% rate of wastage, which equated to a cost of $0.735 million associated with the discarded contents.
The amount of IgG within the discarded nivolumab appeared stable over the course of 4 weeks when kept at either room temperature or in 4°C storage. The mean concentration of IgG in 20-mg vials kept at room temperature was 10.2±0.2 mg/mL at baseline, and it was 10.2±0.1 mg/mL at 28 days. Binding activity to PD-1 with discarded nivolumab also appeared stable over 28 days at either temperature. Similar results were obtained with 100-mg vials for both metrics.
Although evidence of extended stability for nivolumab was demonstrated, clinical efficacy or safety was not evaluated in this study.
The researchers concluded that bodyweight-based dosing of nivolumab leads to significant waste of the product. “Furthermore, practice-level mitigation strategies, including vial sharing and using overfill of the product, can decrease wastage of nivolumab and drug costs,” they concluded in their report.
Fukudo M, Ishikawa R, Mishima K, Ono T, Matsumoto S, Tasaki Y. Real-world nivolumab wastage and leftover drug stability assessment to facilitate drug vial optimization for cost savings [published online June 4, 2020]. JCO Oncol Pract. doi:10.1200/JOP.19.00813