Background: Biosimilars are currently a hot topic and there are many unsolved questions, misunderstandings and sometimes considerable uncertainty, especially among clinicians and patients. Regulatory agencies, such as the European Medicines Agency (EMA) issue guidelines for the development and approval of biosimilars, which are based on scientific principles.
Objective: This article addresses some of the frequently noted misunderstandings and misperceptions. For example, why biosimilars are (or can only be) "similar" but not "identical" compared to the original pharmaceutical product, and aspects, such as the pharmaceutical quality of biosimilars, immunogenicity and the approval process for biosimilars are highlighted.
Keywords: Approval; European Medicines Agency; Guidelines; Original formulation; Regulatory agencies.