siRNA: Sojourn from Discovery to Delivery Challenges and Clinics.

Since the Nobel prize-winning discovery of RNA interference (RNAi) in 1998, considerable money,has been invested in the investigation of therapeutic potential of RNA interference (RNAi) and its,application in human diseases. Encouraging results of ongoing clinical trials for the treatment,of age-related macular degeneration and respiratory syncytial virus have further propelled the investment, research, and hope for a promising outcome. Due to the astonishing efforts in this field, more than 13 siRNA-based formulations are now being evaluated in clinical trials, more than 80 patents have been granted, and more than 500 patent applications have been published in 2009 in the United States alone. Despite this brisk growth, the application of RNAi therapeutics requires the development of safe, effective, and clinically suitable delivery carriers. This review highlights the evolution of siRNA technology, need of siRNA in therapeutics with specific focus on delivery challenges and clinical status, and an overview of its patent thrust. [ABSTRACT FROM AUTHOR]