The goal of this study was to evaluate the effect of Ingavirin® on the morphological features of the foci of adenovirus hepatitis in Syrian hamsters by electron microscopy. The use of the drug was shown to cause a substantial reduction in the rate of destructive processes and inflammatory reactions in the liver, by normalizing its structure at the levels of both tissue and individual hepatocytes. After administration of Ingavirin®, the morphogenesis of adenovirus infection in the infected hepatocytes did not differ from that in the controls; however, the infected cells were fewer. The proportion of morphologically inadequate virions in the presence of Ingavirin® increased from 35 to 46%. The findings suggest that Ingavirin® is an effective drug that has antiviral, anti-inflammatory, and cytoprotective activities in the focus of adenovirus tissue involvement

Parainfluenza viruses affect the upper respiratory tract in all age group patients, in children aged 6 months to 3 years in particular. The most urgent task is to design drugs to treat parainfluenza. This investigation studied the antiviral activity of Ingavirin (2-(imidazole-4-yl) ethanamide of pentandioic-1,5 acid) on a model of parainfluenza infection in Syrian hamsters. The drug was shown to restrict the infectious process in animal lung tissue. This restriction manifested itself as reductions in the infectious titer of parainfluenza virus in the lung tissue, in the degree of pulmonary edema and tissue cell infiltration, and in virus-specific lesion of bronchial epithelial cells. The in vitro experiments demonstrated the ability of Ingavirin to diminish the infective activity of viral descendants. The finding allows one to consider Ingavirin to be a promising antiviral agent that is active against parainfluenza infection in vivo.

Human parainfluenza viruses cause damage of upper respiratory tract in patients of all age groups. The main antiviral drug is Ribavirin, which has severe side effects and is prescribed only at life-threatening conditions. The activity of Ingavirin against human parainfluenza virus was demonstrated in this work both in cell culture and in the model of parainfluenza pneumonia in Syrian hamsters using transmission electron microscopy. The application of Ingavirin is shown to reduce the number of progeny virions and cytopathic effect of the virus. The effect of Ingavirin was similar or exceeded that of ribavirin. In the in vivo experiments Ingavirin was shown to normalize the morphological structure of lungs, decreasing thereby the degree of destruction of alveolocytes. It also restricted budding of progeny virions and reduced the amount of inflammatory infiltrate. Thus, the combination of antiviral, cytoprotective, and anti-inflammatory properties makes Ingavirin an important component of comprehensive therapy of human parainfluenza infection.

Adenoviruses constitute a clinically important family of human pathogens. Due to their wide tissue tropism, adenoviruses are able to induce different diseases from moderate respiratory disorders to fatal outcomes in patients with immunodeficiencies. The authors present the results of a trial of the antiviral activity of the new drug Ingavirin [2-(imidazole-4-yl-ethanamide) pentandioic-1,5 acid] against human adenovirus type 5 on an animal model. Ingavirin is shown to decrease an adenoviral infectious titer in the liver and lung of neonatal Syrian hamsters (by approximately 1 log10 TCID50 as compared to the control) and to reduce the sizes of liver inflammation foci by 2-fold. Furthermore, it also decreases the count of virus-infected cells detectable by morphological analysis. Hepatocytes from Ingavirin-treated animals appear intact unlike strongly vacuolized cells from the animals given placebo. The findings make it possible to regard Ingavirin as a promising agent of the combination therapy of human adenovirus disease.

The effect of meglumine salt of acridonoacetic acid (cycloferon) on the in vivo morphogenesis of influenza infection caused by viruses of different origin (avian, swine and human) and variable susceptibility to antivirals (rimantadine and oseltamivir) has been studied. The administration of cycloferon results in stimulation of the immune response, restriction of the foci of post-influenza pneumonia, and normalization of the structure of respiratory zones independently of the susceptibility or resistance of infectious virus to the drugs. Among virions formed in the lungs of cycloferon-treated mice, prevalence of irregular-shaped virions with defects of surface glycoproteins was observed. The data obtained suggest that cycloferon is a drug with the complex mechanism of activity.

The aim of this investigation was to study the effect of ingavirin on the structure and properties of influenza virions forming in its presence. The infectious activity of the virus and the morphology of the virions were analyzed by titration in cell culture and electron microscopy, respectively. The use of ingavirin was shown to reduce the proportion of morphologically intact virions and to increase that of filamentous and giant particles. No defects of surface glycoproteins were observed. The effect of the drug did not depend on the chosen model of virus replication and it was similarly shown in both cultured human cells and laboratory animals. In MDCK and A549 cells and in the mouse lungs, viral infectious activity was decreased by 1-2 orders of magnitude in relation to a model. The findings suggest that Ingavirin is able to impair the processes of viral morphogenesis, which in turn leads to a reduction in the infectivity of progeny virions.

Despite obvious success in the vaccine development and chemotherapy of influenza, it remains a poorly controlled infection leading to emergence of new pandemic variants of the virus with high morbidity and mortality. We investigated the protective activity of Ingavirin against the lethal influenza A (H1N1) 2009 virus infection on albino mice. Oral use of Ingavirin resulted in sharp decreasing of the mortality (index of protection up to 57%), slight decreasing of the infectious titer of the virus in the lungs (up to 40-fold), normalizing of the body weight dynamics and the lung tissue structure vs. the placebo-treated control. The degree of the bronchial epithelium damage was also strongly decreased. The results allow to consider Ingavirin as an effective antiviral against the current pandemic influenza virus.