Absolute Bioavailability Studies

A major undertaking early in the clinical development process has to do with understanding the Absolute Bioavailability of a compound. That is typically accomplished through a set of studies, starting with one study where the compound is administered via the targeted route (e.g., oral or nasal) and a second study where the dose is given intravenously (IV).

The high sensitivity, accuracy and specificity of AMS towards lightly labeled 14C-tagged compounds provides a marked improvement in these Absolute Bioavailability designs by allowing both routes of administration to be delivered simultaneously in the same subject. In this design, an IV "microdose" of a 14C-tagged drug (microtracer) is administered shortly after the non-tagged therapeutic dose.

[Absolute BA in a single study]The Intravenous microtracer delivers key absorption, availability and metabolism information, while the cold material ensures relevant pharmacokinetics.

With this "hybrid" approach, the equivalent of two clinical studies are performed contemporaneously at minimal additional cost to a single study.

Benefits of this design are that —

  • Absorption
  • Clearance
  • Distribution volumes
  • Metabolite Profiles
  • Routes of elimination
— are determined in a single study. Moreover, the IV microdose ensures simple formulation and obviates the need for supporting IV toxicology testing in animals.

The net effect is to streamline early clinical development by providing highly relevant human data in ways not previously possible.

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