Nanoparticulate protectants for the dry storage of protein therapeutics

Protein therapeutics are a cornerstone of modern medicine, yet their inherent instability often requires expensive and energy-intensive cold-chain logistics to maintain efficacy. Dry-state formulations offer a viable strategy to enhance protein stability, but the associated drying processes, such as lyophilization and spray drying, can introduce stresses that damage protein molecules. While excipients are widely used to protect proteins during dehydration, conventional formulations often require protein-specific, iterative optimization. Further, protein stabilizing excipients can crystallize during storage, thereby reducing product quality, increase product viscosity beyond thresholds for injection, and raise safety concerns. Nanoparticulate excipients are receiving increasing attention to address these challenges. This article provides an overview of nanoparticle excipients showing promise for stabilizing proteins during drying processes. It is envisioned that nanoparticulates may advance toward universal excipients capable of stabilizing a variety of proteins without the need for cumbersome optimization while also providing robust biocompatibility.