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Updated: Apr 3, 2026

Evaluation of the Storage Stability of Extracellular Vesicles
Published on: May 22, 2019
Freeze-drying of HESylated IFNα-2b: Effect of HESylation on storage stability in comparison to PEGylation
Robert Liebner1, Sarah Bergmann2, Thomas Hey2
1Department of Pharmacy, Pharmaceutical Technology & Biopharmaceutics, Ludwig-Maximillians-University Munich, Butenandtstr. 5-8, 81377 Munich, Germany.
Abstract:
A comparison of lyophilized PEGylated and HESylated IFNα was carried out to investigate the influence of protein conjugation, lyoprotectants as well as storage temperature on protein stability. Results show that PEG tends to crystallize during freeze-drying, reducing protein stability upon storage. In contrast, HESylation(®) drastically improved the stability over PEGylation by remaining totally amorphous during lyophilization, with and without lyoprotectants while providing a high glass transition temperature of the freeze-dried cakes.

