Switching to Biosimilars in Inflammatory Rheumatic Conditions: Current Knowledge

Abstract

Biosimilars are more affordable versions of previously approved biopharmaceuticals that are designed to reduce healthcare expenditure and increase patient access to this therapeutic class. To achieve their economic potential, many European countries have started to switch patients from reference drugs to biosimilars. The purpose of this article is to provide a comprehensive perspective on the biosimilar switching controversy, to assess interchangeability regulation and switching policies, and to review current evidence on switching and immunogenicity in the context of inflammatory rheumatic conditions. Patients and physicians feel uncertain about switching highly complex and difficult-to-replicate biosimilars of monoclonal antibodies due to a theoretical risk of increased immunogenicity, especially in extrapolated indications and in a multiple switch scenario involving various biosimilars. However, past experience with smaller biosimilars (somatropin, filgrastim, epoetin), the high standards required for approval of biosimilars of monoclonal antibodies in the European market, and current evidence on switching to infliximab and etanercept biosimilars (especially CT-P13 and SB4) are reassuring. Furthermore, no increased immunogenicity has been reported after switching to biosimilars. Decisions on switching and interchangeability are not covered by the European Medical Agency (EMA) guidelines and are left to individual European states, as opposed to the U.S. Food and Drug Administration (FDA), which has set standards to assess interchangeability. In summary, current knowledge is in favour of switching to biosimilars but the authors consider that this should be a physician-led decision with the active contribution of patients and hospital pharmacists to the pharmacovigilance chain.

Keywords

• Biosimilar
• immunogenicity
• interchangeability
• non-medical switch
• rheumatoid arthritis (RA)
• rheumatic disease