Protein and peptide therapeutics may undergo numerous physical and chemical changes during manufacturing, shipping, storage, and administration that can adversely alter drug potency and safety. Earlier concerns focused upon denaturation (unfolding), oxidation, and deamidation of certain key aminoacyl residues. Recently, aggregation has emerged as a key issue underlying multiple deleterious effects for peptide- or protein-based therapeutics, including loss of efficacy, altered pharmacokinetics, reduced stability and product shelf life, and induction of unwanted immunogenicity. As a result, the US FDA and…