Exceptions to this observation tended to be those compounds known to be absorbed via mechanisms other than passive diffusion (e.g., via transporters or paracellular transporters). There was a tendency for those drugs with canine values of F equal to or greater than 80% to have LogP values equal to or greater than 1.0. There were no clear associations between a drugвЂ™s F in dogs and humans or between the canine value of F and either its human BCS classification, its LogP value, or the canine Do estimate. Whether using 35 or 6В mL to determine Do, the canine solubility classification remained unchanged for all but seven compounds. These same criteria were applied for defining highly soluble and highly permeable in dogs. In addition, in humans, a Do value greater than 1.0 is used to define a compound as highly soluble and a LogP value greater than 1.72 as high permeability. In this analysis, the estimated volume of a water flush administered to fasted dogs (6В mL) and a volume of 250В mL scaled to a Beagle dog (35В mL) were examined. However, the appropriate volume for classifying drug solubility in dogs has not been established. In humans, solubility is determined in 250В mL of fluid. The drugs were also evaluated for any potential association between solubility (calculated from the dose number, Do) or lipophilicity (LogP) and F in dogs.

Therefore, we examined 50 drugs for which absolute bioavailability ( F) was available both in dogs and humans.

To date, the applicability of existing human BCS criteria has not been evaluated in dogs, thereby limiting its use in canine drug development. When used in conjunction with in vitro dissolution tests, the BCS can support the prediction of in vivo product performance and the development of mechanistic models that support formulation assessments through the generation of вЂњwhat ifвЂќ scenarios. The Biopharmaceutical Classification System (BCS) has been a prognostic tool for assessing the potential effects of formulation on the human drug oral bioavailability.

Bcs class 1 drugs list pdf