Introduction

While biological agents have transformed care of patients with rheumatic diseases, access to these agents remains an unmet need in many parts of the world, largely due to their high costs. Biosimilars are biological agents that have been shown to have equivalent safety and efficacy to an already authorized original biopharmaceutical agent. They are associated with reduced costs and have the potential to substantially improve patient access to healthcare. However, unlike generics, these drugs are not exact copies, and due to the complex nature of these molecules, several important issues must be considered by regulators and drug manufacturers. One important consideration is that of switching between originators and biosimilars, which must be shown to be safe. Additionally, nomenclature for biosimilars must be precise enough to enable the biosimilar and originator products to be differentiated, particularly for the purposes of monitoring and pharmacovigilance. In terms of pharmacoeconomics, budget impact analyses suggest that biosimilar agents will be associated with significant direct cost savings and additional patients being treated, potentially translating into earlier therapy escalation, increased patient access and improved long-term outcomes.