title: Predicting accelerated aggregation rates for monoclonal antibody formulations, and challenges for low-temperature predictions.
abstract: Nonnative aggregation is a common degradation route for therapeutic proteins. Control of aggregate levels inherently requires control and/or prediction of aggregation rates at formulation conditions and storage temperatures of practical interest. Additionally, formulation screening often involves generation of accelerated stability data at one or more temperatures. A temperature-scanning approach for measuring nonnative aggregation rates as a function of temperature is proposed and evaluated here for a monoclonal antibody across different formulation conditions. Observed rate coefficients of aggregation (kobs ) were determined from isothermal kinetic studies for a range of pH and salt conditions at several temperatures, corresponding to shelf lives spanning multiple orders of magnitude. Isothermal kobs values were efficiently and quantitatively predicted by the temperature-scanning monomer loss (TSML) approach at accelerated conditions (half lives of the order 10(-1) -10(2) h). At lower temperatures, non-Arrhenius behavior was apparent in some cases, and was semi-quantitatively described by nonlinear van't Hoff contributions to monomer unfolding free energies. Overall, the results demonstrate a novel strategy to quantitatively determine aggregation rates at time scales of industrial interest, based on kobs values from TSML, which are sample- and time-sparing as compared with traditional isothermal approaches, and illustrate challenges for shelf-life prediction with non-Arrhenius kinetics.
authors.affiliation: Department of Chemical Engineering and Center for Molecular and Engineering Thermodynamics, University of Delaware, Newark, Delaware 19716.
authors.forename: Rebecca K
authors.initials: RK
authors.lastname: Brummitt
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Nesta
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Roberts
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D002850:Chromatography, Gel; D004355:Drug Stability; D004356:Drug Storage; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D010316:Particle Size; D066329:Protein Aggregates; D055550:Protein Stability; D058767:Protein Unfolding; D013678:Technology, Pharmaceutical / Q000379:methods; D013696:Temperature
chemical_list: D000911:Antibodies, Monoclonal; D066329:Protein Aggregates