Dose-dependent antiviral activity of released-active form of antibodies to interferon-gamma against influenza A/California/07/09(H1N1) in murine model.

The assessment of dose-response is an essential part of drug development in terms of the determination of a drug's effective dose, finding the safety endpoint, estimation of the pharmacokinetic profile, and even validation of drug activity, especially for therapeutic agents with a principally novel mechanism of action. Drugs based on released-active forms of antibodies are a good example of such a target. In this study, the efficacy of the antiviral drug Anaferon for children (released-active form of antibodies to interferon-gamma) was tested in a dose-dependent manner (at doses of 0.13, 0.2, 0.4, 0.8 ml/mouse/day) in a murine model of acute pneumonia induced by influenza virus pandemic strain A/California/07/09 (H1N1). Administration of the drug at the two highest doses led to: a reduction in the virus infectious titer in lung tissue up to 4.2 lgEID50/20 mg of tissue; infected animals' life prolongation up to 6.7 days; an increase in the survival rate of up to 40% and a decrease in morphological signs of inflammation when compared to the control animals. In this study, the dose-response effect of Anaferon for Children was demonstrated on mice for the first time. This finding is especially important for drugs with a principally novel mechanism of action like drugs based on released-active forms of antibodies. J. Med. Virol. 89:759-766, 2017. © 2016 Wiley Periodicals, Inc.