Cell line development and bioreactor process optimization for an atezolizumab biosimilar

Checkpoint inhibitors are widely recognized immunotherapeutic drugs, known for their effectiveness in treating various cancers. Atezolizumab, targeting the immune checkpoint programmed death-ligand 1, is successfully used to treat several types of cancers. Atezolizumab is a potential biosimilar candidate due to its huge success in the clinic but there is no literature on its production process in mammalian cells. In this study, we generated a monoclonal cell line derived from recombinant Chinese hamster ovary DG44 cells to produce atezolizumab. The selected single clone was employed for media screening and process development. Following production in a 7-L bioreactor, atezolizumab was purified using a three-step chromatographic method. Finally, the purified atezolizumab was characterized and compared with commercial atezolizumab (Tecentriq) through several chromatographic and kinetics analyses.