Principles and applications of selective biophysical methods for characterization and comparability assessment of a monoclonal antibody.

The strategy for a comparability assessment is developed on a hierarchical risk-based approach. Critical analysis of physicochemical and biological characterization assays is essential for the development of a good comparability protocol. Therefore, selection and sensitivity of these assays is very important. This article discusses a case study to evaluate the sensitivity of various methods in a comparability assessment of three lots of an IgG1 monoclonal antibody (mAb). Analysis with eighteen methods demonstrated that only six of the methods were sensitive enough to show a measurable difference of comparability under accelerated conditions (40°C). Samples stored at 4°C were found to be comparable by all methods. A brief comparison of the results of biochemical and functional assays with biophysical analysis is discussed. Basic principles, applications, strength, and limitations of different biophysical methods are also discussed here.