Antisense antiviral compound and method for treating arenavirus infection

A method of inhibiting viral infection in mammalian cells by an Arenavirus in the Arenaviridae family, comprising

• (a) exposing the cells to an antisense oligonucleotide compound composed of morpholino subunits and phosphorus-containing intersubunit linkages joining a morpholino nitrogen of one subunit to a 5′ exocyclic carbon of an adjacent subunit, and characterized by:
• (i) a substantially uncharged, nuclease-resistant backbone,
• (ii) capable of uptake by mammalian host cells,
• (iii) containing between 12-40 nucleotide bases,
• (iv) having a targeting sequence of at least 12 contiguous subunits complementary to SEQ ID NO:1, and
• (v) conjugated to the oligonucleotide, an arginine-rich polypeptide effective to promote uptake of the compound into infected host cells, and
• (b) by said exposing, forming a heteroduplex structure (i) composed of the virus' vRNA or vcRNA strand and the oligonucleotide compound, and (ii) characterized by a Tm of dissociation of at least 45° C.