In recent years, RNA interference technology has been extensively studied for its therapeutic
potential against a wide variety of diseases. It aims to silence the expression of undesired
genes associated with the target disease by the administration of RNA interference agents. However,
these agents (nucleic acids) are unstable in the circulatory system and lack target specificity.
Drug delivery systems are, therefore, crucial for the successful practice of the technique. A wide array
of delivery systems has been developed to conquer these challenges, such as viral vectors, inorganic
drug carriers, polymeric carriers and lipid-based carriers, with, however, significant limitations.
In addition to the existing technologies, novel, innovative drug delivery systems, such as the
configurable xenobot, are emerging at a rapid pace and have the potential to take the realm of
biomedicine to the next level. This review summarizes technical difficulties in the development of
drug delivery systems and current technologies developed for delivering RNAi agents with a discussion
on their limitations.