BIOT 427 |
| Antibody formulation development relies on accelerated stability data at elevated temperatures to optimize formulation parameters. However, the pH- and temperature-dependence of aggregation is complicated for antibody formulations. An inverse pH-dependence for aggregation between normal storage conditions (4C and 29°C) and accelerated conditions (37°C) was discovered for multiple IgG molecules. The nonlinear Arrhenius plots may suggest a conformational perturbation resulting in a different mechanism of self-association at higher temperature. However, biophysical characterization studies demonstrated no thermal unfolding at or below 37°C. Examination of the temperature-dependence of clipping suggested that clipping leading to aggregation was responsible for the increased higher order aggregates at low pH at elevated temperatures. Conformational differences in the hinge region due to disulfide connectivity resulted in differences in clipping and aggregation properties. These results have implications on the mechanisms of antibody aggregation and on the validity of using accelerated data to predict shelf-life. |
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Biophysical and Biomolecular Symposium: Biomolecule Instability, Formulation and Drug Delivery
8:00 AM-11:00 AM, Thursday, 14 September 2006 Hilton San Francisco -- Imperial B Ballroom, Oral
Division of Biochemical Technology |