RESUMO
Stability studies of protein therapeutics are often accelerated by storing potential formulations at elevated temperatures where the rates of various chemical and physical degradation pathways are increased. An often overlooked caveat of using these studies is the potential degradation of the formulation components themselves. In this report, we show that the monoclonal antibody MAB001 aggregated at a faster rate when formulated with sucrose compared to samples that contained sorbitol or no excipient during accelerated stability studies following an initial lag phase where the rates of aggregate formation were similar in all formulations. The duration of the lag phase was both pH and temperature dependent and a significant increase of protein glycation was noticed during this time. These observations indicate that the enhanced rate of antibody aggregation in sucrose containing formulations is likely due to protein glycation following sucrose hydrolysis under accelerated conditions. This hypothesis was confirmed by demonstrating that antibody directly glycated with glucose aggregated at a faster rate than nonglycated antibody stored in the identical formulation. These findings question the utility of using accelerated stability data for predicting protein stability in sucrose containing formulations stored at 2-8 degrees C, where no glycation or change in aggregation rate was observed.
