title: The challenge of biosimilars.
abstract: BACKGROUND
  The purpose of this report was to review issues associated with the introduction of alternative versions of biosimilars used in the oncology setting.
  
  
  METHODS
  Data were obtained by searches of MEDLINE, PubMed, references from relevant English-language articles, and guidelines from the European Medicines Agency.
  
  
  RESULTS
  When biosimilars are approved in EU, they will be considered 'comparable' to the reference product, but this does not ensure therapeutic equivalence. Inherent differences between biosimilars may produce dissimilarities in clinical efficacy, safety, and immunogenicity. Switching biosimilars should be considered a change in clinical management. Regulatory guidelines have been established for some biosimilar categories but, because of the limited clinical experience with biosimilars at approval, pharmacovigilance programs will be important to establish clinical databases. Guidelines also provide a mechanism for the extrapolation of clinical indications (approved indications for which the biosimilar has not been studied). This may be of concern where differences in biological activity can result in adverse outcomes or when safety is paramount (e.g. stem cell mobilization in healthy donors). These issues should be addressed in biosimilar labeling.
  
  
  CONCLUSIONS
  Biosimilars should provide cost savings and greater accessibility to biopharmaceuticals. A thorough knowledge surrounding biosimilars will ensure the appropriate use of biopharmaceuticals.
authors.affiliation: Cancer Centre Karolinska, Department of Oncology, Karolinska University Hospital Solna, Stockholm, Sweden. hakan.mellstedt@karolinska.se
authors.forename: H
authors.initials: H
authors.lastname: Mellstedt
authors.forename: D
authors.initials: D
authors.lastname: Niederwieser
authors.forename: H
authors.initials: H
authors.lastname: Ludwig
mesh_terms: D000970:Antineoplastic Agents / Q000191:economics / Q000627:therapeutic use*; D016527:Drug Costs / Q000331:legislation & jurisprudence; D004348:Drug Labeling; D004335:Drug and Narcotic Control / Q000639:trends; D016568:Drugs, Generic / Q000592:standards / Q000627:therapeutic use; D005062:European Union; D005544:Forecasting; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy; D011358:Product Surveillance, Postmarketing / Q000639:trends*; D011994:Recombinant Proteins / Q000191:economics / Q000592:standards / Q000627:therapeutic use*; D013810:Therapeutic Equivalency
chemical_list: D000970:Antineoplastic Agents; D016568:Drugs, Generic; D011994:Recombinant Proteins