Stability of Insulin Detemir Injection in Different Primary Packaging Systems at Room Temperature

To assess the stability of insulin detemir at controlled room temperature (RT) at 25°C in different packaging systems over 7 days.

The degradation characteristics of insulin detemir were determined based on the assay results in different packaging systems (pinhole glass vial, closed glass vial, glass syringe, and plastic syringe) at RT using a reverse-phase high-performance liquid chromatography (HPLC) assay method for insulin injection. Each packaging system was compared to insulin detemir stored in the original packaged closed glass vial at 2°C to 8°C.

Insulin detemir stored in a closed glass vial and a glass syringe showed minor degradation at the end of day 7 (98.96% ± 1.49% and 99.78% ± 0.10%, respectively). Insulin detemir stored in plastic syringe decreased to 94.90% ± 2.50% by day 3 and to 93.52% ± 0.29% by day 7. Storage in pin-hole glass vial showed an increase in the assay (152.13% ± 0.12%) by day 7.

Stability studies in different packaging systems demonstrated that insulin detemir remained stable for at least 7 days in a closed glass vial or glass syringe, but for only 3 days in a plastic syringe at RT. This study will allow pharmacists in the hospital setting to deliver patient-specific insulin doses into an insulin syringe with confidence in the stability.