Henning Gieseler, PhD

Henning Gieseler, PhD, works in the Department of Pharmaceutics at the University of Erlangen, Erlangen, Germany 91058. tel. +49 9131 85 29545, gieseler@freeze-drying.eu.

The authors evaluate the thermal properties of gentamicin sulfate as a small-molecule drug model in optimizing the freeze-drying cycle.

For true freeze-drying cycle optimisation, information on the maximum allowable product temperature during primary drying is required.

Lyophilisation is often necessary for pharmaceutical products to improve stability or shelf-life. However, the process can present difficulties, particularly when scaling up from the laboratory to commercial production. We bring experts together to discuss best practices for developing a lyophilisation process, including quality by design (QbD) and design space.

Cycle design and robustness testing using advanced process analytical technology.

Mannitol is the most commonly used bulking agent in freeze-drying formulation design. The benefit of using mannitol is that it crystallizes during freezing and permits drying processes at higher product temperatures, and thus with higher sublimation rates relative to purely amorphous systems (1). Mannitol, however, is known to form different crystalline modifications which compromises reproducibility of product characteristics and storage stability due to phase transformations (2, 3).