There are normally four steps to approve (or not ) a medicine: step 1: it must be proven that this drug is not toxic step 2: it must be proven that this drug is active on sick people step 3: it is compared to other drugs which have the same indication step 4: is the pharmacovigilance. The drug is monitored during all its commercialization.
During the approval of biosimilar agents, step 2 is omitted because we need to establish that there are “no clinically meaningful differences” in the efficacy and safety<span> of the biosimilar when compared to the original, which can be done in step 3.</span>