Journal of Bioprocessing & Biotechniques

 Prior to the introduction of regulated process validation activities it was generally assumed that the production process for protein drugs per se is under control and appropriate for their generation, if the final product fulfils the criteria raised for the bioanalytical quality end control for therapeuticals. However nowadays, the production process is being considered in a much deeper and considerably more differentiated fashion. The use of in-process and on-/at-line controls and supervisions on a regular basis encompassing all critical parameters about the individual sub-processes and the emerging intermediary and side products is generally thought to significantly contribute to the demonstration that the production process is under control at the time point of the measurements and with high probability also thereafter. The deep understanding of the interrelationship between process and product can not completely eliminate but will considerably reduce the risk for the emergence of product variants, impurities and contaminants during critical sub-processes that may escape detection during final quality control for technical and/or economical reasons. The test systems required for elucidation of the multiple process-product interactions have to be chosen, validated and calibrated according to commonly accepted and approved criteria. In the near future novel platform technologies, such as protein chips and biosensors that are based on novel capturing/immobilising probes, e.g. glycosylphosphatidylinositol-anchored proteins, and detection probes, e.g. nanoparticles, will greatly contribute to the rapid and reliable measurement of many samples for multiple parameters in cell-free and cell-based assay configurations in parallel rather than consecutive fashion.