Protein instability is one of the main challenges to overcome during the research and development of biopharmaceuticals. Usually, the protein drugs are processed into solid-state formulations to prolong the shelf life. Lyophilization, also known as freeze-drying, is the most applied method to produce protein formulations in a solid form. Lyophilization is done in two steps: 1) the freezing of the formulations, 2) the sublimation of the ice under vacuum conditions. Both freezing and sublimation can cause stresses on the processed protein. Therefore, the proteins are stabilized by adding excipients. However, characterization of the exact stabilization mechanism of the excipient is very challenging.
Therefore, a joint alliance between the Technical University of Denmark, Technical University of Munich, and the Ludwig Maximilian University of Munich was investigating this matter using a combination of experiments and computational modeling.
Two different studies that focused on granulocyte colony-stimulating factor (GCSF) and Reteplase were conducted during the joint research.
The first study is about modeling the pH-dependent aggregation behavior of GCSF using combinations of advanced molecular dynamics simulations and biophysical techniques.
The second study focused on identifying the protein-specific effect of excipients by considering two different proteins; Reteplase and GCSF. The investigations were done by running simulations of the full cycle of the freeze dying simulations.
Our results show that the molecular dynamics simulations can provide valuable insight into the complex phenomena that can occur during the development and processing of protein-based drugs.