Bioequivalence

A similarity between two drugs that implies that they both will have the same effect on a patient is called bioequivalence. Bioequivalence implies that two drugs release their active component in the bloodstream in the same quantities in the same rate. When evaluating how good a generic drug works it bioequivalence is compared to the name-brand version.

For a generic drug to obtain the U.S. food and drug administration’s stamp of approval, the manufacturer of the new drug must prove that it is bioequivalent to the branded version. FDA approval before marketing or selling a different version of a branded drug is necessary too. For example it must be proved that a once-a –week tablet is bioequivalent to a daily tablet. Apart from this, depending upon how the drug is taken, i.e. as a pill, injection, patch, inhaler or through another method, the regulatory authority has its own standards in bioequivalence. If a generic drug is not bioequivalent to a name-brand drug then it cannot be used as a substitute for it but rather approved for a different use.

The generic drugs need not undergo the various clinical trials the established brand drug has to. This is because the generic drug has to be only bioequivalent. The company seeking approval to market the generic drug has only to test it against the name-brand drug on two small groups of test subjects, extract timed blood samples from each patient and show through statistical study that any difference in the drug’s bioavailability in participants taking the brand name version versus participants taking the generic version is not clinically substantial.

It is simpler to make a bioequivalent variant of a traditional pill or injectable drug than to make a bioequivalent form of a biologic drug. As a result the generic version of the biologic drugs called “Biosimilars” will have to undergo clinical trials to obtain approval. These bioequivalence services are offered by all the leading CRO company in India.