CMAB008 is an infliximab biosimilar candidate. The host cell of Remicade is mouse myeloma SP2/0 cell, however, the host cell of CMAB008 is CHO (Chinese hamster ovary cell). It seems that CMAB008 has lower immunogenicity and higher safety, because Remicade comprises more complex-type and hybrid-type glycans than CMAB008. However, it is not yet known whether CMAB008 is not inferior to Remicade. This randomized, double-blind trial investigates the efficacy and safety of CMAB008 for moderately to severely active rheumatoid arthritis, compared to Remicade.