Understanding bioequivalence

Bioequivalence is the term used when comparing brand name and generic drugs.

Before a generic drug can be sold, the manufacturer must scientifically demonstrate that its product is "bioequivalent" to the brand name drug. If the generic and brand drug are bioequivalent, it means there is no significant difference between them. They are equal in terms of dosage, safety, strength, quality, the way they work in the body and the way they are taken.

Generic drug companies must demonstrate bioequivalence

Bioequivalence is the international standard for determining that two drugs are similar enough to be used interchangeably. It is demonstrated by showing that the generic medication will deliver consistent amounts of active ingredients into a patient’s bloodstream, measured over time, as compared to the brand drug equivalent.

One way to show bioequivalence is to take blood samples after a subject is given a brand drug and then again after the subject takes the generic, or vice versa, to prove the generic drug’s release of its active pharmaceutical ingredient into the blood stream over time is comparable to the brand.

An example of a bioequivalence study is illustrated in the graph below.

The graph shows the concentration of the brand drug (in red) and the generic drug (in blue) in the bloodstream at various points in time.

In general, bioequivalence testing provides a useful comparison between generic and brand name drugs containing the same active ingredients. It also plays a key role in the development of new generics and gives you access to safe, high quality medicine at more affordable prices.