Effect of Freezing on Lyophilization Process Performance and Drug Product Cake Appearance.

This study highlights the significance of the freezing step and the critical role it can play in modulating process performance and product quality during freeze-drying. For the model protein formulation evaluated, the mechanism of freezing had a significant impact on cake appearance, a potential critical product quality attribute for a lyophilized drug product. Contrary to common knowledge, a freezing step with annealing resulted in 20% increase in primary drying time compared to without annealing.