The present invention provides antisense antiviral compounds, compositions, and methods of their use and production, mainly for inhibiting the replication of viruses of the Filoviridae family, including Ebola and Marburg viruses. The compounds, compositions, and methods also relate to the treatment of viral infections in mammals including primates by Ebola and Marburg viruses. The antisense antiviral compounds include phosphorodiamidate morpholino oligonucleotides (PMOplus) having a nuclease resistant backbone, about 15-40 nucleotide bases, at least two but typically no more than half piperazine-containing intersubunit linkages, and a targeting sequence that is targeted against the AUG start site region of Ebola virus VP35, Ebola virus VP24, Marburg virus VP24, or Marburg virus NP, including combinations and mixtures thereof.
