Status and progress in the development of rDNA-derived Tocilizumab and its biosimilars for treatment of rheumatoid arthritis

The immune system unintentionally targets the synovial lining of the joints in rheumatoid arthritis (RA), a chronic autoimmune disease that causes inflammation, discomfort, and gradual joint destruction. A humanized anti-IL-6R monoclonal antibody (mAb), tocilizumab (TCZ) is primarily used to treat rheumatoid arthritis (RA) as well as a number of other chronic and inflammatory conditions, particularly polyarticular juvenile idiopathic arthritis (pJIA), systemic juvenile idiopathic arthritis (sJIA), and castleman disease. From the identification of interleukin-6 (IL-6) as a crucial inflammatory mediator and its receptor IL-6R to the clinical development of TCZ, this study provides an overview of TCZ. Because of its many therapeutic uses, TCZ has gained widespread use, and several biosimilars have lately entered clinical studies or hit the market. We summarize the upstream production strategies for full-length and fragment mAbs across various eukaryotic and prokaryotic expression systems. Additionally, the review discusses the development, manufacturing, and clinical assessment of TCZ and its biosimilars, including immunogenicity and pharmacokinetic profiles, to ensure their safety and efficacy. Finally, various developmental strategies are outlined for the successful production of biologically functional recombinant TCZ from different host systems.