Evaluation of Protein Aggregation Under Various Stress Conditions Using the Aggregates Sizer

Introduction

Biopharmaceuticals have recently gained attention for their specificity in attacking pathogens, relative lack of side effects, and potent effect. However, compared with low molecular weight pharmaceuticals, bio- pharmaceuticals are more susceptible to stress, and more likely to aggregate. When a biopharmaceutical aggregates due to stress, this results in a decrease or disappearance of its pharmacological effect, along with the potential for causing serious side effects such as shock symptoms from an immunological reaction. Consequently, a framework is being established that evaluates the stability of biopharmaceuticals in terms of their susceptibility to likely stresses (heat and physical stresses during transport, storage, and at use). Protein preparations are a type of biopharmaceutical and aggregate to form sub visible particles (SVP) in the size range of 0.2 to 10 μm. Problems with conventional methods of evaluating protein aggregates have been the inability to analyze the SVP size range in a single measurement, inability to take measurements while stress is applied, inability to recover samples after measurement, and inability to perform quantitative measurements. The Aggregates Sizer biopharmaceutical aggregation analysis system was developed to overcome these problems. This article describes how we applied heat and physical stress to intravenous immunoglobulin (IVIG), then evaluated aggregate formation using the Aggregates Sizer. We show how different aggregate formation processes and speeds occur based on stress type and stirrer bar material by quantifying aggregates in the SVP size range.

January 14, 2016 GMT