Serum Interleukin 6 Before and After Therapy with Tocilizumab Is a Principal Biomarker in Patients with Rheumatoid Arthritis

Abstract

Although both TNF-α and IL-6 are major targets of therapeutic intervention in RA, baseline serum IL-6 but not baseline TNF-α level is a potential biomarker reflecting disease activity. Measurement of serum IL-6 in RA before treatment may be useful to estimate residual disease activity after TCZ treatment and to predict responsiveness to TCZ treatment.