Tocilizumab for treating rheumatoid arthritis: an evaluation of pharmacokinetics/pharmacodynamics and clinical efficacy

Introduction: Dysregulated overproduction of IL-6 has important roles in the pathogenesis of rheumatoid arthritis (RA). Tocilizumab (TCZ) is the only approved biologic agent inhibiting the IL-6 pathway for RA treatment, and is the focus of this review.Areas covered: This review summarizes the pharmacologic characteristics, clinical efficacy and safety profile of TCZ therapy in RA patients. The data reviewed were based mainly on Phase III randomized clinical trials and the literature until 2014 regarding TCZ in RA treatment.Expert opinion: Being a first-line biologic agent for RA, TCZ is especially suitable for RA patients who have shown an inadequate response to TNF-α inhibitors or who cannot tolerate methotrexate. In view of its advantage in suppressing acute-phase reactions and as the only approved inhibitor of IL-6 signaling, TCZ might be particularly effective for RA patients with a high systemic inflammatory response, anemia, AA amyloidosis and other diseases mediated by IL-6. Being able to identify reliable predictors of response to TCZ, and finding more effective new biologic and treatment options, will reduce the number of patients who fail to respond to TCZ.