data correlate with protective action of drugs in case of nonsurvivable death grippal infection in mice antiviral activity of the experimental lethal grippal pneumonia in white mice induced with a virus influenza the model of lethal grippal infection of white scrub mice of both genders with weight 10 12 g from rappolovo nursery was used for testing of peptide complexes antiviral activity a aichi 2 68 h3n2 flu strain has been used in the work adapted to white mice in laboratory conditions with high pathogenicity inducing infection with developing pneumonia and lethal outcome during 5 10 days depending on the viral dose peptides and their derivatives were once administered abdominally to animals 6 and 12 hours before contamination in the amount of 1 2 u03bcg kg of animal weight nss or phosphate buffer in equal volume was placebo in control animal group virus was previously titrated on animals and lethal concentration for mice has been determined the animals were exposed to virus intranasally with slight ether anesthesia in the dose of 0 2 and 5 ld 50 each study group comprised 10 mice the animals were observed during 15 days i e the term when 100 animal death is observed in experimental flu weight and death of animals was recorded day to day in control and experimental groups based on received mortality data mortality rates in each group number of died for 15 days animals to total amount of contaminated animals in the group ratio protective index the findings are represented in the fig5 analysis of findings showed that the action of studied drugs a1 relative to influenza a virus pathogenic for mice was comparable to efficiency of the protective effect of reference drug remantadin 80 87 u2014 with dose of virus 1 ld 50 high protective effect of zn.