Use of excipients to control aggregation in peptide and protein formulations

Aggregation is rapidly emerging as a key issue underlying multiple deleterious effects for peptide or protein-based therapeutics, including loss of efficacy, altered pharmacokinetics, reduced stability or product shelf life, and induction of unwanted immunogenicity. In addition, bioavailability and pharmacokinetics of a self-associating peptide can be influenced by aggregate size and the ease of disruption of the non-covalent intermolecular interactions at the subcutaneous site. This review highlights the various types of aggregates encountered in peptide and protein formulation, methods useful in detecting aggregates, and recent developments in the use of excipients to prevent or reduce peptide and protein aggregation.