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Published on: June 7, 2015
Recovery and biological activity of filgrastim after injection through silicone rubber catheters
J M McCullough1, E Sprentall-Nankervis, C A Potcova
1Department of Pharmacy, Botsford General Hospital, 28050 Grand River Avenue, Farmington Hills, MI 48336, USA.
Abstract:
The recovery and biological activity of filgrastim after injection through a silicone rubber catheter were studied. Various volumes of filgrastim injection 300 micrograms/mL (0.17, 0.34, 0.51, 0.68, 0.85, and 1.0 mL) were injected through silicone rubber catheters and collected in glass vials to simulate intravenous bolus injections. The catheters were flushed with 3 mL of 5% dextrose injection before and after the injections. For some catheters, the procedure was repeated to simulate the administration of a second filgrastim dose through the same catheter. The theoretical filgrastim concentration in the expelled fluid was 16.1, 30.5, 43.6, 55.4, 66.2, or 75.0 micrograms/mL (corresponding to the filgrastim injection volumes). Filgrastim concentrations in expelled fluid were measured with an enzyme-linked immunosorbent assay, and biological activity was measured with a mitogenic cell-culture assay. There was > or = 10% loss of filgrastim after the first injection when the injection volume was 0.17, 0.34, or 0.68 mL. Mean drug recovery after the second filgrastim injection exceeded that after the first for all six volumes and was > or = 90% for five volumes. The recovered filgrastim retained all of its activity. A > or = 10% loss of filgrastim occurred for three of six volumes after one injection through a silicon rubber catheter. Recovery was higher after a second injection through the same catheter. Biological activity was not affected.
Insights
Filgrastim recovery through silicone catheters showed a drug loss with smaller injection volumes. However, the recovered filgrastim maintained its biological activity, with improved recovery after a second injection.
Area of Science:
- Pharmacology
- Biotechnology
- Medical Devices
Background:
- Silicone rubber catheters are commonly used for drug delivery.
- Ensuring drug integrity and efficacy after administration through medical devices is crucial.
- Filgrastim is a vital biologic for stimulating neutrophil production.
Purpose of the Study:
- To evaluate the recovery and biological activity of filgrastim after injection through silicone rubber catheters.
- To determine the impact of injection volume and repeated use on filgrastim recovery.
- To assess if filgrastim retains its biological function post-catheter administration.
Main Methods:
- Filgrastim solutions of varying volumes were injected through silicone catheters.
- Drug concentrations in expelled fluid were measured using enzyme-linked immunosorbent assay (ELISA).
- Biological activity was assessed via a mitogenic cell-culture assay.
Main Results:
- A loss of filgrastim (≥10%) occurred with smaller injection volumes (0.17, 0.34, 0.68 mL) after the first use.
- Drug recovery improved after a second injection through the same catheter, exceeding 90% for most volumes.
- Recovered filgrastim demonstrated no loss in biological activity.
Conclusions:
- Silicone rubber catheters can lead to filgrastim loss, particularly with smaller volumes.
- Repeated use of the same catheter improves filgrastim recovery.
- The biological activity of filgrastim is preserved following administration through silicone catheters.
