Bioavailability Studies
Objective:
=> To define various terms relating to bioavailability studies
=> To understand some of the past problems with bioavailability
=> To evaluate the components and results of a bioavailability
study
Studies, which are carried to evaluate different dosage forms. These studies
called bioavailability or drug product evaluation studies might compare:-
i) one type of dosage form with another, e.g. regular tablet with sustained
release tablet. For this type of tablet ka values should be slower; but F values
should be similar or
ii) two (or more) dosage forms made by two different manufacturers.
Second brand or generic drug manufacturers are required to prove that their
product is equivalent to previously marketed products which have demonstrated
clinically efficacy. For most drugs, the second and subsequent manufacturer must
show that their product is bioequivalent, i.e. same ka and F, as the product(s)
on the market. During the development of new drugs and drug products, the
original manufacturer will also perform bioavailability studies on new products,
probably comparing the product to be marketed with an intravenous dosage form if
at all possible.
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