Development of a discriminating in vitro dissolution method for the poorly soluble drug rimonabant: Effect of formulation variables on dosage form release profiles

Abstract

The effect of formulation parameters on the in vitro release profile of a poorly soluble drug was investigated using rimonabant as model drug. A dissolution test was developed to evaluate the release profile of rimonabant from both 20- mg film-coated tablet and capsule dosage forms. The test was applied to compare dissolution profiles of different dosage forms and to evaluate the effect of formulation parameters on the in vitro release profile of the drug. Four different commercially available products were evaluated, and the results obtained show very distinct rates and extent of dissolution among them. The type of excipients used in the capsule formulation significantly influenced the dissolution rate of the formulations studied.