Biosimilar is similar to another biologic medicine almost identical copy of original product. Biosimilars are highly similar to the reference product in terms of safety, purity and potency, but may have minor differences in clinically inactive components. Drug-related authorities such as the EU’s (EMA), US’s (FDA) and the Health Products and Food Branch of Canada hold their own guidance on requirements for demonstration of the similar nature of two biological products in terms of safety & efficiency.