Topical Drugs for Diabetic Complications Current and Future

Diabetes is a major metabolic disease, and the number of patients is still growing in both industrialized and developing countries. Drugs to reduce blood glucose levels by several mechanisms have been launched in past decades, and the options for treating hyperglycemia have been extended. However, it is still difficult to control blood glucose level strictly, and moreover, current therapies using hypoglycemic agents have not shown sufficient effect to prevent the development of microvascular complications that result in impaired quality of life (QOL) of patients. Therefore treatments for these diabetic complications are urgently needed. Drugs for diabetic peripheral neuropathy currently in use are mainly for management of diabetic neuropathic pain, and do not cure the underlying cause of the disease. In diabetic retinopathy, intravitreal injection of anti-VEGF agents is a current approach, but the administration route is insufficient. Diabetic nephropathy is treated with angiotensin-I converting enzyme (ACE) inhibitors and angiotensin-II receptor blockers (ARBs), which were originally prescribed for hypertension. These situations indicate the lack of effective target-oriented medication for diabetic compliations, and drugs with novel mechanism should be developed. In this chapter, we summarize drugs for three major diabetic complications currently in use and in clinical trial phases. It is hoped this will help the reader to understand the trend of current pharmacological approaches and the tide of next-generation drugs in this field.

Keywords: ACE inhibitor, analgesia, Anti-VEGF, ARB, ARI, blood circulation disorder, clinical trials, diabetes, diabetic complications, diabetic macular edema, diabetic nephropathy, diabetic neuropathy, diabetic retinopathy, metabolic disorder, microalbuminuria, microvascular complications, new drugs, painful diabetic neuropathy, RAS inhibitor.