Why is it difficult to bring biosimilars into the market ?
Biosimilars are the generic versions of biotech drugs. In case of pharmaceuticals, a patent expiration follows a spate of smaller pharma companies flooding the market with cheaper versions of the same drug. This is easily acheived due to two reasons:
a) Any pharma manufacturing company has a long time at its disposal to investigate the exact composition of a drug while it is in patent and hence can reverse engineer it down to the minutest component.
b) Particulalrly in the US, a drug patent application should necessarily be accompanied with the ‘best method’ of formulation. This document also becomes public for any pharma company to see.
Because of both these reasons, the generic formulations generated in the market are near-exact versions of the original drug which can be safely prescribed to a patient. But its not the same for Biosimilars! The processes used for production of a biotech drug are very different from a pharmaceutical. The process relies primarily on microorganisms which when stimulated in controlled environments, produce the desired drug. But since microorganisms are involved, even the slightest change in the bacterial strain may lead to a appreciably altered product. Hence, even if a generic manufacturer has an exact idea of the drug components, it is near to impossible to produce an exact replica of a biotech drug. Yes, the basic protein may be the same, but the glycosylation profile may be different to mention just one of the many possibilities. And as soon as a change is introduced, the drug can start behaving very differently in the body. Hence, the logic behind allowing pharma generics does not hold true for biosimilars which the main reason behind finding approval for biosimilars.