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The effect of loading process on product collapse during large-scale lyophilization
Alexis J Wallen1, Susan H Van Ocker, Jessica R Sinacola
1Merck & Co., Inc, West Point, Pennsylvania 19486, USA. alexis_wallen@merck.com
Journal of Pharmaceutical Sciences
|July 29, 2008
Summary
Lyophilization chamber loading impacts final product appearance. Inadvertent annealing during loading caused decreased surface area and product collapse in early-loaded vials, affecting cake quality.
Area of Science:
- Pharmaceutical Science
- Bioprocessing Engineering
Background:
- Lyophilization enhances pharmaceutical product stability by solvent removal.
- Variability in lyophilization can stem from freezing, vial placement, and drying stages.
- Inconsistent lyophilization affects cake appearance, moisture, and stability.
Purpose of the Study:
- To investigate the impact of lyophilization chamber loading on product inhomogeneity.
- To identify causes of variability in final cake appearance.
Main Methods:
- A complex biological product was flash-frozen.
- The product was subsequently loaded into a large-scale lyophilization chamber.
- The effect of loading method on cake appearance was analyzed.
Main Results:
- Chamber loading significantly affected cake appearance for the first vials loaded.
- This effect is attributed to inadvertent annealing during the loading process.
- Annealing likely reduced dried cake surface area, leading to secondary drying collapse.
Conclusions:
- Lyophilization chamber loading is a critical factor influencing product homogeneity.
- Inadvertent annealing during loading can compromise final product quality.
- Optimizing loading procedures is essential for consistent lyophilization outcomes.
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