At week 12, 60% of individuals switched to adalimumab had an ACR20 response and 33% had an ACR50 response; 76% got a moderate and 23% got an excellent EULAR response. 1st biologic can be noticed from 5% to 15% and from 9% to 15.4%, respectively (except in two research). Intro Three anti-tumor necrosis factor-alpha (anti-TNF) therapies are authorized for arthritis rheumatoid (RA) by the united states Food and Medication Administration: infliximab (Remicade?), adalimumab (Humira?), and etanercept (Enbrel?). Two even more will come quickly (certolizumab pegol and golimumab). Although commonalities predominate when you compare the three obtainable anti-TNF real estate agents obviously, a accurate amount of medical variations in effectiveness or protection have already been mentioned [1,2]. Initial, the half-lives – 3 times for etanercept, 10 times for infliximab, and 13 times for adalimumab – may result in variations in the duration of TNF neutralization . Also, both monoclonal antibodies, adalimumab and infliximab, have quite strong affinity for TNF, raising the percentage of neutralized TNF substances. Furthermore, the complexes shaped when monomeric and trimeric soluble and membrane-associated TNF substances bind towards the Closantel anti-TNF agent are more steady with infliximab and adalimumab than with etanercept. Finally, the monoclonal antibodies are highly specific for TNF, whether soluble or at the membrane level, whereas etanercept binds to lymphotoxin- in addition to soluble TNF, leading to the control of another possible pathogenetic pathway. Soluble TNF binds to the fusion protein, becoming unable to act on its cellular receptor. Thus, etanercept has a buffering effect on TNF, and this effect is probably reversible and does not result in permanent elimination of TNF molecules. Furthermore, binding of etanercept to membrane-associated TNF does not cause cell lysis. Infliximab and adalimumab can bind two soluble or membrane-associated TNF molecules, forming a stable and long-lasting complex and causing cell lysis (for example, macrophages and some T-cell Closantel subsets) or RHEB cell function impairments . These differences may influence the risk of immune response impairment and the ability to ward off infections, explaining the greater risk of tuberculosis with infliximab and adalimumab than with etanercept. Immunogenicity seems extremely weak for etanercept and adalimumab but higher for infliximab, inducing antibodies to its murine component (human anti-murine antibodies, or HAMA) and leading to allergic reactions and the often-seen escape phenomenon . All of these data have led physicians to treat RA patients who experience treatment failure with one anti-TNF agent (due to either inefficacy or toxicity) by switching to a second anti-TNF agent, although the clear-cut benefits of switching are unknown because no controlled trial has ever been conducted. Rituximab, or anti-CD20, is an antibody used in RA, whereas abatacept is a dimeric fusion soluble protein made of the extracellular part of CTLA-4 present on T cells and Fc of IgG1. It links CD80/86 on antigen-presenting cells with a higher affinity than CD28, thus preventing the costimulation. Tocilizumab is a humanized antibody that links both soluble and membranous interleukin-6 receptor. The differences in the mechanism of action should allow clinicians to rescue patients not fully responding to a TNF blocker since a different pathway is targeted; however, a definite analysis of the gain of Closantel effect in terms of disease activity score (DAS) remission or of an American College of Rheumatology 70% improvement criteria (ACR70) response – that clearly allows clinicians to identify the crucial pathway alternative to TNF – has not been provided. The aim of this study was to investigate the evidence in the literature about the efficacy of switching between different biologics in RA patients. Materials and.