7 Indian Journal of Pharmaceutical Sciences January - February 2006 www.ijpsonline.com Review Review Review Review Review Article Article Article Article Article Needle Needle Needle Needle Needle-F -F -F -F -Free Insulin Drug Delivery ree Insulin Drug Delivery ree Insulin Drug Delivery ree Insulin Drug Delivery ree Insulin Drug Delivery PREETI PATNI, DHANILA VARGHESE, NEELAM BALEKAR AND D. K. JAIN* College of Pharmacy, IPS Academy, Rajendra Nagar, A. B. Road, Indore-452 012, India. For most patients with type 1 diabetes, the worst part of the disease is to tolerate needle after needle, both for glucose measurement and to deliver insulin. In the last two decades, concept of insulin therapy by multiple-dose injection has undergone a miraculous change. Needle-free insulin delivery appeared to be a wonderful approach, and its allure rested in being comfortable and safe. In today’s era, insulin delivery by alternative route is a topic of current interest in the design of drug delivery system. Major global pharmaceutical companies are showing encouraging progress in their attempts to develop alternative insulin delivery technologies. Many such drug delivery systems have been developed for oral, buccal and nasal route. T his review article discusses, in brief, the novel and emerging technologies that are in pipeline, including insulin inhalers, insulin spray, insulin pill, insulin analogues, insulin complement, islet cell transplant, implantable insulin pumps and guardian continuous glucose monitoring system. Diabetes is a major public-health problem and is emerging as a pandemic. As estimated, 135 million people worldwide had diagnosed diabetes in 1995, and this number is expected to rise to at least 300 million by 2025 1 . Diabetes mellitus represents a group of diseases of heterogeneous etiology, characterized by chronic hyperglycemia and other metabolic abnormalities. The etiological classification of diabetes includes type 1, type 2, those due to specific mechanisms or diseases, and gestational diabetes. Diabetes mellitus type 1 is characterized by destructive lesions of pancreatic β cells by an auto-immune mechanism. Type 2 diabetes is characterized by a combination of decreased insulin secretion and sensitivity 2 . Attempts to attain strict glucose control when managing diabetes have traditionally utilized daily subcutaneous injections of human insulin. This strategy has offered improvements in glycemic control but is unable to replicate fully the normal, diurnal plasma profile of endogenous insulin 3 . The development of novel non- invasive routes of insulin administration promises to further improve diabetes management. Many barriers to initiate insulin therapy include need for frequent insulin injection, fears that insulin injections will be painful and difficult to administer, concerns about hypoglycemia and weight gain. Thus, each measure that reduces these barriers will help to prevent inappropriate delays in starting insulin therapy as well as to promote better compliance with therapy 4 . New developments are happening all the time, and the new technologies, some of which are under development and some which are developed to hit the market, are insulin inhalers, insulin spray, insulin pill, insulin analogues, insulin complement, islet cell transplant, implantable insulin pumps and guardian continuous glucose monitoring system. NEW TECHNOLOGIES FOR INSULIN DELIVERY Insulin inhalers: Inhaled insulin appears to be a non-invasive, well- tolerated and liked modality of treatment with potential for both type 1 and 2 diabetes 5 . Results of short-term studies indicate that glycemic control achieved with an inhaled insulin regimen is comparable with a subcutaneous insulin regimen in patients with type 1 6 and type 2 7 diabetes. It has been determined in patients with type 1 diabetes that improvement in overall patient satisfaction with inhaled insulin is rapid and sustainable compared with conventional subcutaneous insulin, and the reduced treatment burden has a positive impact on psychological well-being 8 . Inhaled insulin greatly enhances patient satisfaction, quality of life and acceptance of intensive insulin therapy in a diabetic patient 9,10 . Several drug *For correspondence E-mail: dkj57@rediffmail.com