189 Bushra Ahmedi. et al. / International Journal of Pharmacy & Therapeutics, 5(3), 2014, 189-202. e- ISSN 0976-0342 Print ISSN 2229-7456 International Journal of Pharmacy & Therapeutics Journal homepage: www.ijptjournal.com IJPT CHALLENGES OF ORAL DRUG DELIVERY SYSTEMS Bushra Ahmedi *1 , Anna Balaji 1 and M.S. Uma Shankar 1 1 Department of Pharmaceutics, Trinity College of Pharmaceutical Sciences, Peddapally, Karimnagar, Andhra Pradesh, India. ABSTRACT Advances have developed and commercialized in oral controlled release products. The significant challenges in developing controlled release formulations for drugs with poor aqueous solubility require different techniques for both solubilization and engineering of release profile. New therapeutics like peptides, proteins, oligonucleotides and vaccines demand for novel controlled release technologies. Challenges for the oral vaccines like instability and poor absorption in GIT have been overcome by lipid formulations. Developing a controlled release formulation for a water insoluble drug is challenging. Complexation and hydrogel reported as carrier for the intestinal delivery of peptides. Compression coating is an extension of tableting technology. Injection molding is a thermal process where polymer or polymer mixture is melted and injected to a mold to form a finished product eg. microneedle for transdermal delivery. Melt extrusion, injection moulding, and drug coating provides flexibility to design oral controlled release formulations. Controlled release delivery of poorly soluble compounds could be pursued through several approaches with combination of solubilization. Formulation designs with computer modeling help to achieve desired release profile of drugs. It is optimistic that oral dosage form of biopharmaceuticals including proteins, peptides, vaccines and nucleotides will become reality eventually with the advancement of the novel technologies. Diabetes mellitus is a common disease and its complications leads to excess morbidity, mortality, loss of independence and reduced quality of life. Diabetes mellitus is responsible for major health care problems and costing billions of dollars annually. Novel approaches for insulin delivery are explored, including oral, nasal, rectal, transdermal, pulmonary, uterine, ocular delivery and subcutaneous implants. Making needles needless is gaining widespread prominence over the disadvantages of subcutaneous route. The oral route is most acceptable and convenient route of drug administration for chronic therapy. Extensive investigations are being conducted to achieve successful control of blood glucose by the oral delivery system. Key Words:- Challenges, Oral controlled release, Peptides and Vaccines. INTRODUCTION Significant challenges in developing controlled release formulations for drugs with poor aqueous solubility require both solubilization and engineering of release profile. New therapeutics under development is large molecules such as peptides, proteins, oligonucleotides, and vaccines. Their physical, chemical, and biopharmaceutical attributes demand novel controlled Corresponding Author Bushra Ahmedi Email:- ahmedibushra@gmail.com release technologies to reduce barriers for oral delivery, such as instability in GI tract and poor absorption. The continuous improvement is also important regarding the decrease of cost and the increase of efficiency. The advancements include novel excipients, processes, and equipments for formulation scientists to develop oral controlled release formulation (Rao VM et al., 2001). ORAL CONTROLLED DELIVERY FOR WATER- INSOLUBLE DRUGS Drug products have to be dissolved in GI fluids to get absorbed. For a water-insoluble drug, the absorption