Issue: Vol. 42

Oral delivery would be the favoured route of drug administration (1). Other routes include intranasal, allowing fast delivery to the brain, pulmonary using aerosolised compounds, transdermal, buccal and intravenous or transdermal AI controlled closed loop infusion pumps (2). To enhance delivery, drug formulations can be enclosed in lipid e.g. liposomes or encapsulated to protect and direct delivery or treated to increase solubility e.g. spray drying (3). In the oral route attempts may be made to protect the stomach from damaging effects such as those of NSAIDs (4). In terms of oral delivery for a compound to be absorbed it must overcome three major barriers, the digestive barrier, the mucus barrier and the epithelial barrier in sufficient amounts to yield a therapeutic effect. The mucus barrier is also relevant in intranasal and pulmonary delivery. Current models to test absorption now include an in vitro gut model including the 3 barriers combined with absorption (5). In addition this article will also discuss examples where natural products could replace chemically synthesised drugs. The pharmaceutical industry increasingly relies on outsourcing to CROs for research and drug delivery development activities. What are seen as challenges by the pharmaceutical industry have become opportunities for CROs (6).