SAXS study on protein-protein interactions on understanding the impact of formulation and temperature during freezing and frozen storage of

Therapeutic proteins are often stored as frozen drug substance to limit degradation of the expensive raw material between large campaign production and final
product processing. Despite slowing overall degradation rates, the freezing process and subsequent storage impose several stresses on the protein, leading to
unfolding and affecting the colloidal stability in the freeze concentrate (FC) by changing protein-protein interactions (PPI), ultimately leading to aggregation.
The proposed SAXS/WAXS study will continue LS3210, in which formulation and freezing process-dependent differences in protein-protein distances (PP
distances) in freezing solutions and corresponding FCs were studied.
Our study aims to expand a comprehensive understanding of protein behavior in the FC to enable a more rational formulation design. We aim to analyze PPI
(reflected by S(q)0) in protein solutions of increasing total solid content and extrapolate the net interparticle interaction behavior to the FC.