Clinical Study of Single Dose IL-6R mAb Injection in RA Patients

This study is aim to evaluate the safety, tolerability, PK/PD characteristics, immunogenicity parameters and Preliminary Efficacy of Recombinant Humanized IL-6R Monoclonal Antibody Injection in Patients With Active Moderate-to-Severe Rheumatoid Arthritis. There are 4 dose groups and each group enrolls 10 patients: 4mg/kg(IL-6R mAb); 6mg/kg(IL-6R mAb); 8mg/kg(IL-6R mAb) and 8mg/kg(tocilizumab ).each patient receives a single intravenous(i.v.) dose. The infusion time is from 60 to 90 minutes (the speed can be adjusted appropriately if there are injection reactions).