New Developments in Oral Insulin Delivery

Abstract

Diabetes is a leading cause of chronic illness, and the costs associated with its treatment exceed $245 billion annually in the United States alone. For those patients afflicted with diabetes who need daily insulin injections for the management of the disease an effective oral insulin formulation would offer many advantages over the current parenteral administration. Indeed, it has been proposed that inadequacy in the current method of administration may actually contribute to or exacerbate some of the many complications of the disease. Consequently, there is an urgent need to develop a more effective delivery system that avoids the flaws inherent in the current parenteral route of insulin administration. The goal of this chapter is to review the current state of research in the development of oral insulin formulation. Research has shown that there are two major barriers to oral insulin delivery, namely: enzymatic degradation of the polypeptide insulin and its transport limitations across the gastrointestinal membrane and mucus layers. Advances in medicinal chemistry and biomaterials science have resulted in the emergence of promising strategies designed to overcome these barriers. In this review, we discuss these advances and discuss the challenges that remain in the path to successful development of clinically viable products.