Polymer nanocarriers for the delivery of small fragments of nucleic acids: oligonucleotides and siRNA.

The success of the application of new therapeutic methods based on RNA interfering strategies requires the in vivo delivery of active ODN or siRNA down to the intracellular compartment of the target cells. This article aims to review the studies related to the formulation of RNA interfering agents in polymer nanocarriers. It will present the different types of polymer nanocarriers used as well as the biological activity of the resulting ODN and siRNA loaded nanocarriers. As will be explained, the part of the in vitro studies provided useful data about the intracellular delivery of the formulated RNA interfering agents. Investigations performed in vivo have considered animal models of different relevant diseases. Results from these investigations have clearly demonstrated the interest of several polymer nanocarriers tested so far to deliver active RNA interfering effectors in vivo making possible their administration by the intravenous route.