**3.2 ASO's delivery**

Although the clinical relevance of ASOs has been demonstrated, inefficient cellular uptake, both *in vitro* and *in vivo*, limit the efficacy of ASOs and has been a barrier to therapeutic development. Cellular uptake can be <2% of the dose resulting in too low ASO concentration at the active site for an effective and sustained outcome [22]. Indeed, many researches are conducted on the improvement of ASO delivery via the use of delivery vehicles.
