title: Biosimilars: implications for rheumatoid arthritis therapy.
abstract: Abbreviated pathways for the approval of biosimilars have been established in the European Union (EU), the United States, and other countries. Biosimilar TNF inhibitors have been available in South Korea and the EU since 2012 and 2013, respectively, and the first biosimilar infliximab was introduced to the clinic in the United States in November 2016. Five TNF inhibitor biosimilars have now been approved, and many other biosimilars to treat rheumatoid arthritis and other inflammatory diseases are in development.
  
  
  
  Over the last 18 months, published results of randomized clinical trials (RCTs) have shown equivalent efficacy and comparable safety and immunogenicity of biosimilars with their reference products. 'Real world' experience with biosimilars in the EU continues to increase and provides evidence regarding the efficacy and safety of using biosimilars in the clinic and of switching from bio-originators to their biosimilars.
  
  
  
  Cost implications of using biosimilars and extrapolation of their use to treat diseases in which they were not tested in RCTs are of great interest. We review the results of RCTs and available experience with biosimilars in the clinic.
authors.affiliation: aClinical Professor of Internal Medicine, UT Southwestern Medical School bMedical Director, Metroplex Clinical Research Center, Dallas, Texas cDirector of Clinical Research, Rheumatology Division, Professor of Medicine and Timothy S. and Elaine L. Peterson Chair in Rheumatology, Department of Medicine, UMass Memorial Medical Center and University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Stanley
authors.initials: S
authors.lastname: Cohen
authors.forename: Jonathan
authors.initials: J
authors.lastname: Kay
mesh_terms: D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D059451:Biosimilar Pharmaceuticals / Q000627:therapeutic use*; D006801:Humans; D016896:Treatment Outcome
chemical_list: D059451:Biosimilar Pharmaceuticals