Gi tract challenges - achieving in vitro in vivo correlations (IVIVCs) for controlled release dosage forms

Introduction Controlled release (CR) pharmaceutical dosage forms have several uses. They can (i) protect a drug, (ii) facilitate site-specific drug delivery, or (iii) prolong drug release in vivo. Whilst this approach offers significant advantages for the delivery of certain drugs (e.g. low solubility compounds, labile molecules or irritant substances) it extends dosage form exposure to the hostile environment of the gastrointestinal (GI) tract.