Efficacy and Safety Study of Tacrobell to Treat Rheumatoid Arthritis

Inclusion Criteria: * Male or female aged ≥20years * Signed and dated informed consent document indicating that the patient * Women of childbearing potential must have a negative serum or urine pregnancy test at the screening visit. Except in the case of surgically sterile or amenorrhea for one year. * Female patients must agree to use adequate contraception measures during the period of therapy which should be continued for 4 weeks. * have RA and meet all of the following criteria; RA occurring ≥ 3months and less than 15 years and diagnosed based on 1987 ACR classification criteria for rheumatoid arthritis; Active RA patients with MTX and among them who has insufficiency response to DMARDs as defined DAS28\>3.2 in active RA patient. Insufficiency response is defined despite MTX therapy for \> 12 weeks, RA activity≥ more than moderate and confirmable during 12 weeks, sequence of taking MTX \>7.5mg/week for more than 6 weeks; ESR≥28mm/h or CRP≥1.0mg/dl; Tender Joint Counts must be more than 6 and Swollen Joint Counts must be more than 3 Exclusion Criteria: * Inflammatory joint diseases, Systematic inflammatory disease * Prosthesis and had an event of infected in it. * Medical history of chronic infection, moderate infection or possibly to life threatening or signs and symptoms of serious infection. * Patients have received treatment with a live vaccine from baseline within 8 weeks. * HBsAg positive and hepatitis C virus positive patient. * Patients have a history of malignancy. (But, carcinoma in situ of the uterine cervix or basal cell carcinoma have been treated is allowed within 5years) * Patients have cardiovascular disease or associated disease which is not controlled. * uncontrollable blood sugar(HbA1C ≥8%) or required insulin. * Patients with a history of operation on index knee joint which could have influence on the result and need to have surgery as determined by investigator. * At screening, patients have laboratory result as defined by ; white blood cell(WBC) \< 3,500/mm3, Absolute Neutrophil Count(ANC) \< 1,500/mm3, Hemoglobin \< 8.5g/dl, Platelet count(PLT) \< 100,000/mm3, Serum creatinine \>1.5\*upper limit of normal or 2mg/dl, Total bilirubin \> 2\*upper limit of normal, aspartate aminotransferase(AST) \> 2\*upper limit of normal, alanine aminotransferase(ALT) \> 2\*upper limit of normal, alkaline phosphatase(ALP) \> 2\*upper limit of normal * Patients on any other clinical trial or experimental treatment in the past 8weeks * An impossible one who participates in clinical trial by investigator's decision