Study to Demonstrate Non-Inferior Efficacy and Safety of CinnoRA® Versus Humira® for Treatment of Active RA

The purpose of this study is to compare the efficacy and safety of adalimumab produced by CinnaGen company and AbbVie adalimumab in subjects with active Rheumatoid Arthritis. Patients with the diagnosis of active Rheumatoid arthritis according to EULAR criteria (European League Against Rheumatism) aged between 18 to 75 years will be included. This study is a Phase III, randomized, two arms, double-blind (patient and assessor blinded), parallel active-controlled non-inferiority clinical trial. The eligible patients are randomized in a 1:1 ratio to receive CinnoRA® or Humira®. Every two weeks, 40 mg of either of the drugs will be administered to each patient subcutaneously along with methotrexate (15 mg/week), folic acid (1 mg/day), and prednisolone (7.5 mg/day) over six months. The primary objective of the study is to compare the efficacy of test- adalimumab (CinnoRA®) and the reference adalimumab (Humira®) in patients with moderately to severely active rheumatoid arthritis regarding the evaluation of EULAR criteria based on Disease activity score (DAS). The secondary objectives of this study are: * To further compare the efficacy of test- adalimumab to reference adalimumab * To assess the safety of test- adalimumab compared to reference adalimumab