Bioavailability Definition & Meaning
This chapter provides readers an overview of general concept of BA and BE. Details on typical BA/BE study designs, study conducts, bioassays, and data analyses are discussed, with a primary focus on orally administered drugs. Special topics on BE for narrow therapeutic drugs and highly variable drugs, together with application of partial areas under the curve for BE testing are also presented. A common clinical experience where an appreciation for bioavailability becomes important is the interactions between warfarin and albumin in the plasma. Albumin-warfarin binding inactivates warfarin and reduces the fraction of active, free warfarin in the systemic circulation. When albumin sequesters warfarin in the blood, both the clearance and bioavailability of warfarin is reduced. 3 Comparative bioavailability of generic drugs (ANDA) Such formulations are usually not being accepted as therapeutically equivalent to the existing reference drug. For certain drugs, in vivoequivalence was don...