Synthesis and biological activity of water-soluble polymer complexes of arbidol

We have synthesized water-soluble complexes between the antiviral drug arbidol and polymer compounds with molecular masses of 19-31 kDa representing copolymers of acrylamide (AA) and 2-acrylamido-2-methylpropanesulfonic acid (AAMPS). The complexes are less toxic than arbidol and retain the high level of antiviral activity of this drug. The content of arbidol in the obtained complexes is within 26.4-32.1 mass%. The antiviral activity of the synthesized polymeric complexes against all studied viruses, including human epidemic influenza virus A (H3N2), bird highly pathogenic influenza virus A (H5N1), herpes type 1 virus (HSV-1), and adenovirus type III (AV-III) is comparable to the antiviral effect of nonmodified arbidol. The in vitro toxicity of the obtained complexes is about one order of magnitude lower than that of nonmodified arbidol; the pharmacological index, four times that of the initial low-molecular-weight drug. The synthesized water-soluble polymer complexes of arbidol can be useful in pharmacology since they can serve as the basis for new effective and safe parent antiviral substances and related formulations.