Table I.

Generics vs. biosimilars: Key differences.

Characteristic	Biosimilars	Generics
Chemical structure compared with the reference molecule	Complex molecules, post-translational modifications, slight differences in structure, same primary amino acid sequence	Simple molecules, well-defined structure, same amino acid sequence.
Immunogenicity	Can be immunogenic	No immunogenic potential
Interchangeability	Additional switching studies required to fulfill interchangeability requirements	Switchability between generic and reference product is ensured. Interchangeability among generics is not covered.
Manufacturing process	Complex biotechnological process	No need for complex modifications, easy manufacturing.
Time for marketing approval	7–8 years	2–3 years
Preclinical studies	Required	Not required, only bioequivalence studies.
Storage	Very sensitive, need special conditions	Easy to store, stable.