The present invention provides a multi-targeting nucleic acid construct comprising at least: (a) a first nucleic acid portion that is at least partially complementary to at least a first portion of RNA transcribed from a target gene； (b) a second nucleic acid portion that is at least partially complementary to at least a second portion of RNA transcribed from a target gene, which target gene may be the same or different to the target gene defined in (a)； (c) a third nucleic acid portion that is at least partially complementary to the first nucleic acid portion of (a), so as to form a first nucleic acid duplex region therewith； (d) a fourth nucleic acid portion that is at least partially complementary to said second nucleic acid portion of (b), so as to form a second nucleic acid duplex region therewith. The construct is designed so that subsequent to in vivo administration the construct disassembles to yield at least first and second discrete nucleic acid targeting molecules that respectively target RNA transcribed from the target genes of (a) and (b). Typically, the first nucleic acid targeting molecule is capable of modulating expression of the target gene of (a), and comprises, or is derived from, at least the first nucleic acid portion of (a). Typically, the second nucleic acid targeting molecule is capable of modulating expression of said target gene of (b), and comprises, or is derived from, the second nucleic acid portion of (b).La présente invention concerne une construction d'acide nucléique à ciblage multiple comprenant au moins : (a) une première partie d'acide nucléique qui est au moins partiellement complémentaire d'au moins une première partie d'ARN transcrit à partir d'un gène cible ； (b) une seconde partie d'acide nucléique qui est au moins partiellement complémentaire d'au moins une seconde partie d'ARN transcrit à partir d'un gène cible, lequel gène cible peut être identique ou différent du gène cible défini en (a) ； (c) une troisième partie d'acid
