I call him Boy GeorgeFor approval, the manufacturer of a generic drug must demonstrate, among other things, that the generic is bioequivalent to the brand-name drug. By contrast, biosimilar manufacturers must demonstrate that the biosimilar is highly similar to the reference product, except for minor differences in clinically inactive components. Biosimilar manufacturers must also demonstrate that there are no clinically meaningful differences between the biosimilar and the reference product in terms of the safety, purity, and potency of the product (i.e., safety and effectiveness).
Mom (or maybe the straight guy lol) can put this in English for the mere humans on the forum.
My understanding is the prescribing doc must write the Rx for the biosimilar. Pharmacy is not allowed to substitute.