title: Stabilization of proteins in solid form.
abstract: Immunogenicity of aggregated or otherwise degraded protein delivered from depots or other biopharmaceutical products is an increasing concern, and the ability to deliver stable, active protein is of central importance. We review characterization approaches for solid protein dosage forms with respect to metrics that are intended to be predictive of protein stability against aggregation and other degradation processes. Each of these approaches is ultimately motivated by hypothetical connections between protein stability and the material property being measured. We critically evaluate correlations between these properties and stability outcomes, and use these evaluations to revise the currently standing hypotheses. Based on this we provide simple physical principles that are necessary (and possibly sufficient) for generating solid delivery vehicles with stable protein loads. Essentially, proteins should be strongly coupled (typically through H-bonds) to the bulk regions of a phase-homogeneous matrix with suppressed β relaxation. We also provide a framework for reliable characterization of solid protein forms with respect to stability.
authors.affiliation: Materials Measurement Lab, National Institute of Standards and Technology, Gaithersburg, MD 20899-8543, USA; Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742, USA. Electronic address: cicerone@nist.gov.
authors.forename: Marcus T
authors.initials: MT
authors.lastname: Cicerone
authors.affiliation: Pharmaceutical Sciences Dept., University of Connecticut, Storrs, CT 06269, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pikal
authors.affiliation: Materials Measurement Lab, National Institute of Standards and Technology, Gaithersburg, MD 20899-8543, USA.
authors.forename: Ken K
authors.initials: KK
authors.lastname: Qian
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D004355:Drug Stability; D006801:Humans; D018054:Hydrobromic Acid; D011506:Proteins / Q000008:administration & dosage / Q000737:chemistry* / Q000276:immunology
chemical_list: D003692:Delayed-Action Preparations; D011506:Proteins; D018054:Hydrobromic Acid
keywords: Aggregation; Dynamic stabilization; Lyophilization; Protein stability; Water substitution