Background: Biosimilars have the potential to create competition, lower costs, and increase patient
access to biological medications. However, biological medications are sensitive to their manufacturing processes
and difficult to precisely characterize, leading to questions about substitution and interchangeability among products.
Methods: This article reviews the role of biosimilars in patient access to therapeutic antibodies.
Results: Although pathways for the approval of biosimilars have been developed, important issues remain unresolved.
Interchangeability, or the designation of one medicine as clinically similar to and/or substitutable for
another, is specified in some countries but restricted or awaiting policy resolution in others. Non-medical switching,
or the switching among biological medications to select a less expensive product, for reasons unrelated to
patient health and safety, is controversial because of the potential for complications related to repeated switching
(e.g., immunogenicity and loss of therapeutic effect), and transfer of prescribing responsibility for patient medications
from the physician to the insurance company. Although biosimilars have different names in different countries,
the World Health Organization (WHO) calls for nomenclature that incorporates the international nonproprietary
name of the original biological medication followed by a distinguishing suffix qualifier. Naming consistency
across countries seems sensible, and adoption of the WHO recommended suffix would greatly simplify
Conclusions: Support for the WHO proposal is advised by numerous stakeholders, and resolution of the remaining
outstanding issues is urged so that patients and physicians can safely access biosimilars.