Etanercept is a dimeric genetic recombinant glycoprotein consisting of Fc domain 
of human Immunoglobulin G1 and the extracellular domain of human tumor necrosis 
factor (TNF) receptor type II. Etanercept exerts therapeutic effects on 
inflammatory diseases such as rheumatoid arthritis and juvenile idiopathic 
arthritis by neutralizing biological activities of TNFα/Lymphotoxin (LT) α. 
Mochida Pharmaceutical and LG Chem have developed syringe, pen, and vial 
products of Etanercept BS (biosimilar) as the first biosimilar of Enbrel in 
Japan. The active ingredient of those products "Etanercept biosimilar 1" has the 
identical primary structure to that of Enbrel. The development of the Etanercept 
BS, including evaluations of quality attributes, nonclinical and clinical 
studies was performed in accordance with "Policies on Assurance of Quality, 
Safety and Efficacy of Biosimilars". The quality attributes of Etanercept BS 
were similar to those of Enbrel, and the binding affinities to TNFα/LTα, TNFα 
neutralizing activity, nonclinical pharmacokinetics and toxicological profiles 
of Etanercept BS were comparable to Enbrel. Additionally, the pharmacokinetic 
profile and efficacy of Etanercept BS were equivalent to those of Enbrel and 
there was no clinically significant difference in safety profiles between them 
in Phase I and Phase III clinical studies. The marketing approval application of 
the Etanercept BS with the same indications as Enbrel filed by Mochida 
Pharmaceutical was approved in January 2018 and the products will be launched by 
Ayumi Pharmaceutical in the near future. The Etanercept BS, which is as highly 
effective as Enbrel is expected to make beneficial therapies more easily 
accessible to patients.