[Comparative study of the antiviral activity of rimantadine and bonafton]

The results of the study on toxicity and the antiviral activity of bonaphthone and rimantadine are presented. A high toxicity of bonaphthone for developing chick embryos was demonstrated, the maximum non-toxic dose of bonaphthone being about 10 microgram/embryo, while for rimantadine it was above 1000 microgram/embryo. In white mice, however, the toxicity of these two drugs was approximately similar. The minimal single lethal dose for mice by the oral route was 400-500 mg/kg for rimantadine and bonaphthone, by the intraperitoneal route 65 mg/kg for bonaphthone and 125 mg/kg for rimantadine. Bonaphthone had a slight prophylactic activity protecting mice inoculated with A2/Bethesda/63 influenza virus. The index of effectiveness of bonaphthone was about 40%, that of rimantadine under similar experimental conditions over 90%. Bonaphthone had no therapeutic effect. It inhibited multiplication of A2/Hong Kong/68 influenza virus in the lungs of mice inoculated with minimal doses of the virus, but was inactive in case of infection of mice with A/Port Chalmers/73 virus. Thus, the comparative study of bonaphthone and rimantadine revealed no superiority of bonaphthone.