The quality, safety and efficacy of medicines are a basic and an essential requirements of the pharmaceutical industry and the regulatory authorities. Analytical methods are used to obtain data on drug product properties and to control bioprocess parameters. The reliability of analytical methods, which is proved by method validation, is the basis for obtaining correct data. Together with data integrity they form the basis of the quality system.
In this master's thesis full validation of two complementary analytical methods is presented. The analytical methods used measure relative biological activity of the biosimilar monoclonal antibody that is an active pharmaceutical ingredient from the group of tumor necrosis factor alpha (TNF-α) inhibitors. The analytical methods function by two different principles and are therefore complementary. The first analytical method functions via cell apoptosis inhibition (AIA): it measures the activity of antibody's antigen binding site (Fab region) and with it the specificity of antibody binding to TNF-α. The second analytical method primarily measures the activity of antibody's constant region (Fc region) and with it its binding to FcgIIIa cell receptors (CD16). It is based on the principle of antibody-dependent cellular cytotoxicity (ADCC).
The validation experiments and the result evaluation were performed according to ICH and FDA guidelines as well as good manufacturing practice. Both analytical methods were evaluated with the following validation parameters: accuracy, linearity, range, precision, specificity and robustness. The results of those validation parameters were then compared between methods.
Accuracy and linearity results show that both analytical methods give accurate results in the range of 50–200 % relative potency of the samples. Reproducibility and intermediate precision results demonstrate that both analytical methods are precise, however the AIA method is slightly more variable. The geometric relative standard deviation (GRSD) values for reproducibility and intermediate precision are 1% and 3% for the AIA method, and 4% and 9% for the ADCC method, respectively. Specificity analyses show that excipients present in the drug substance matrix do not affect the functioning of either of the two bioassays nor the accuracy and precision of the results. Robustness results demonstrated that the tested method parameter variations, such as incubation times and cell concentrations, do not affect the accuracy and precision of the results. In terms of robustness it was also confirmed that drug substance samples are stable 7 days after opening and storage at 2–8 °C.
The validation results of all parameters prove that the acceptance criteria for both analytical methods are fulfilled and that both analytical metods are suitable for use in the quality control testing.