Antiviral effect of a derivative of isonicotinic acid enisamium iodide (FAV00A) against influenza virus.

With only a single class of antiviral drugs existing for treatment of influenza (neuraminidase inhibitors), the search for novel effective compounds is urgently needed. We evaluated a low molecular mass compound, enisamium iodide (FAV00A), against influenza virus infections in primary differentiated normal human bronchial epithelial (NHBE) cells, and in ferrets. FAV00A (500 µg/ml) markedly inhibited influenza virus replication and reduced viral M-gene expression in NHBE cells. Treatment of ferrets with FAV00A (200 mg/kg once daily for 7 days) initiated 24 h after inoculation with 105 TCID50 of influenza A/Wisconsin/67/2005 (H3N2) virus resulted in a significant decrease in virus titers in the upper respiratory tract. Our data show that FAV00A exhibits an antiviral effect against influenza virus in NHBE cells and provides some benefits in a ferret model. Thus, further Keywords: antiviral agents; enisamium iodide; influenza virus; MDCK cells; NHBE cells; ferrets.