Current Pharmaceutical Biotechnology                      Michele M. Luchetti * , Devis Benfaremo and Armando Gabrielli Dipartimento Scienze Cliniche e Molecolari, Sezione di Clinica Medica, Università Politecnica delle Marche, Ancona, Italy A R T I C L E H I S T O R Y Received: March 22, 2017 Revised: November 06, 2017 Accepted: December 18, 2017 DOI: 10.2174/1389201019666171226151852 Abstract: Background: Biologic drugs, introduced in clinical practice almost twenty years ago, repre- sent nowadays a prominent treatment option in patients with chronic inflammatory arthritis, such as Rheumatoid Arthritis, Psoriatic Arthritis and Spondyloarthritis, that include ankylosing spondylitis and non-radiographic axial spondyloarthritis. Methods: Several compounds targeting different pathways have been marketed and approved for the treatment of inflammatory arthritis, with a significant impact on the clinical outcomes and the natural history of the diseases. Results: There are currently seven classes of biologics that are available for the treatment of inflamma- tory arthritis, each inhibiting a different aspect of the immune-driven inflammatory pathway. They include: • Tumor Necrosis Factor (TNF) inhibitors (infliximab, adalimumab, etanercept, golimumab and cer- tolizumab pegol); • Interleukin-1 (IL-1) receptor antagonists (anakinra); • Interleukin-6 (IL-6) inhibition (tocilizumab); • Interleukin-12/23 (IL23) inhibition (ustekinumab); • Interleukin-17 (IL-17) inhibition (secukinumab); • B-cell inhibition (anti-CD20, rituximab); • T-cell costimulation inhibition (anti-CTLA-4, abatacept). Conclusion: In this review, we will focus on the role of biologic drugs in the treatment strategies for inflammatory arthritis. Keywords: Biologic drugs, TNF inhibitors, rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, efficacy, safety. 1. INTRODUCTION Biologic drugs, introduced in clinical practice almost twenty years ago, represent nowadays a prominent treatment option in patients with chronic inflammatory arthritis, such as Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA) and Spondyloarthritis (SpA), that include ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr- AxSpA). The biologics used in inflammatory arthritis are geneti- cally engineered proteins derived from human genes that in- hibit specific components of the immune system involved in enhancing or inhibiting inflammation. Whereas conventional *Address correspondence to this author at the Dipartimento Scienze Clini- che e Molecolari, Sezione di Clinica Medica, Polo Didattico, Università Politecnica delle Marche, Via Tronto 10/A, 60020 Ancona, Italy; Tel: +39-071-2206101; +39-071-2206195; E-mail: m.luchetti@univpm.it drugs affect the immune system as a whole, biologics affect specific components of the immune system in a more spe- cific way, and therefore less adverse events are expected. Several strategies, including neutralizing cytokines by using soluble receptors or monoclonal antibodies, receptor blockade, and activation of anti-inflammatory pathways, are used to treat inflammatory diseases involving cytokines [1]. Several compounds targeting different pathways have been marketed and approved by Food and Drug Administration (FDA) and European Medicine Agency (EMA) for the treat- ment of inflammatory arthritis, with a significant impact on the clinical outcomes and the natural history of the diseases. There are currently seven classes of biologics that are available for the treatment of inflammatory arthritis, each inhibiting a different aspect of the immune-driven inflamma- tory pathway. 1873-4316/17 $58.00+.00 © 2017 Bentham Science Publishers Send Orders for Reprints to reprints@benthamscience.ae Current Pharmaceutical Biotechnology, 2017, 18, 989-1007 989 REVIEW ARTICLE Biologics in Inflammatory and Immunomediated Arthritis