Lyophilisation, commonly known as freeze-drying, is a critical unit operation in the pharmaceutical industry used to preserve and stabilise both small and large-molecule drug products and biologics, including monoclonal antibodies, vaccines and peptides. Lyophilisation is a process that involves freezing a liquid drug product and then removing the frozen solvent via sublimation, providing a stable solid matrix of the drug product and other excipients. This method is particularly suitable for heat-sensitive molecules, as it dramatically mitigates hydrolysis degradation found in liquid products, is more product-sensitive and practical than other drying methods and avoids the difficulties of multi-component powder filling.
Biopharmaceutical companies have increasingly favoured lyophilisation for the formulation of their pharmaceutical products. Primarily, the driving factor leading to the increased use of lyophilisation is the ability to stabilise the drug product and excipients in a solid matrix, increasing the shelf life of the product. This, along with the removal of solvents, has a positive impact on storage and distribution requirements. For instance, many lyophilised drug products experience an increase in thermal stability and no longer require frozen storage. This provides a more cost-effective, lower-risk, and efficient way to optimise storage and distribution. This is particularly beneficial for drug products that are shipped to countries with tropical climates or lower infrastructure, where temperature may affect the stability of a product, and cold chain storage may not be available.
As companies continue to pioneer new molecules and treatments, it is clear that the stability of these molecules has increasingly become a detrimental factor upon every iteration, and that lyophilisation is the pathway to a solution. At PCI, we believe lyophilisation cycle development is not only a science, but an art; each drug product that comes into the laboratory presents unique challenges, and the design of a cycle requires an understanding of individual chemistry, characteristics, and interaction to yield a high-quality product in every cycle. While there is a myriad of tools and techniques to perform, the below is an overall guide to the lyophilisation process and some of the steps needed for success.
The Lyophilisation Cycle
Lyophilisation involves a series of steps to achieve optimal product stability and quality. While there are individual intricacies within these steps, they can be broadly categorised into three phases: freezing, primary drying, and secondary drying.
