The invention provides compositions and associated methods for the antisense treatment of genetic disorders, infections and various other medical conditions. In particular, embodiments of the present invention are directed to pharmaceutical compositions comprising a combination of an antisense oligonucleotide compound conjugated with a positively charged polymer (“ON-PCP”) and a negatively charged polymer. Pharmaceutical compositions in accordance with the present invention have demonstrated improved antisense efficiency and reductions in cell toxicity compared to compositions that contain an oligonucleotide compound conjugated with a positively charged polymer.