vx-787 and Orthomyxoviridae-Infections

Pimodivir exerts an antiviral effect on the early stages of influenza A virus replication by inhibiting the cap-binding function of polymerase basic protein 2 (PB2). In this study, we used a combination of sequence analysis and phenotypic methods to evaluate pimodivir susceptibility of influenza A viruses collected from humans and other hosts. Screening PB2 sequences for substitutions previously associated with reduced pimodivir susceptibility revealed a very low frequency among seasonal viruses circulating in the U.S. during 2015-2020 (<0.03%; 3/11,934) and among non-seasonal viruses collected in various countries during the same period (0.2%; 18/8971). Pimodivir potently inhibited virus replication in two assays, a single-cycle HINT and a multi-cycle FRA, with IC

Topics: Animals; Antiviral Agents; Drug Resistance, Viral; Enzyme Inhibitors; Humans; Influenza A virus; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Influenza A Virus, H7N9 Subtype; Influenza, Human; Microbial Sensitivity Tests; Orthomyxoviridae Infections; Pyridines; Pyrimidines; Pyrroles; RNA-Dependent RNA Polymerase; Viral Proteins; Virus Replication

With the aim to identify novel influenza PB2 inhibitors with high potency and excellent pharmacokinetic parameters, we have designed and synthesized two new series of pyrimidine-fused heterocycle derivatives based on two generations of co-crystal structures. Docking studies with the newly disclosed PDB structure guided the second round of rational design and led to the discovery of 25m, 25o and 25p as representative compounds with improved potency (EC

Topics: Animals; Antiviral Agents; Drug Design; Heterocyclic Compounds; Humans; Influenza A virus; Influenza, Human; Mice; Molecular Docking Simulation; Orthomyxoviridae Infections; Pyrimidines; Viral Proteins

JNJ63623872 (formerly known as VX-787) is an inhibitor of influenza A virus polymerases through interaction with the viral PB2 subunit. This interaction blocks the cap-snatching activity of the virus that is essential for virus replication. Previously published work has documented antiviral activity of JNJ63623872 in cell culture and mouse infection studies. In this report, we extend the in vivo observations by comparing the efficacies of JNJ63623872 and oseltamivir in mice infected with influenza A/California/04/2009 (H1N1pdm) and A/Victoria/3/75 (H3N2) viruses. Animals received JNJ63623872 or oseltamivir orally twice daily for 10 days starting 2 h pre-infection. JNJ63623872 (2, 6, and 20 mg/kg/day) and oseltamivir (20 mg/kg/day) completely prevented death in the H1N1pdm virus infection. Weight loss at nadir was only 12% in mice receiving 2 mg/kg/day of JNJ63623872 compared to 23% and 32%, respectively, in oseltamivir-treated (20 mg/kg/day) and placebo groups. Lung hemorrhage scores, lung weights, and lung virus titers on day 6 were reduced in a dose-responsive manner by JNJ63623872 treatments, whereas oseltamivir treatments were not as effective. JNJ63623872 was less active against H3N2 virus infection, with more body weight loss occurring and only 30% survival at the 2-mg/kg/day dose. Lung scores, lung weights, and H3N2 viral titers in lungs of mice were reduced less by JNJ63623872 treatments compared to the H1N1pdm infection. Nevertheless, the 20-mg/kg/day dose of JNJ63623872 was more effective than oseltamivir (20 mg/kg/day) in improving body weight and reducing the severity of lung infection. JNJ63623872 appears to be an important new drug candidate to treat influenza A H1N1pdm and H3N2 virus infections.

Topics: Animals; Antiviral Agents; Drug Discovery; Drug Therapy, Combination; Indoles; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Lung; Mice; Orthomyxoviridae Infections; Oseltamivir; Pyridines; Pyrimidines; Pyrroles; Viral Load; Virus Replication

In our effort to develop agents for the treatment of influenza, a phenotypic screening approach utilizing a cell protection assay identified a series of azaindole based inhibitors of the cap-snatching function of the PB2 subunit of the influenza A viral polymerase complex. Using a bDNA viral replication assay (Wagaman, P. C., Leong, M. A., and Simmen, K. A. Development of a novel influenza A antiviral assay. J. Virol. Methods 2002, 105, 105-114) in cells as a direct measure of antiviral activity, we discovered a set of cyclohexyl carboxylic acid analogues, highlighted by VX-787 (2). Compound 2 shows strong potency versus multiple influenza A strains, including pandemic 2009 H1N1 and avian H5N1 flu strains, and shows an efficacy profile in a mouse influenza model even when treatment was administered 48 h after infection. Compound 2 represents a first-in-class, orally bioavailable, novel compound that offers potential for the treatment of both pandemic and seasonal influenza and has a distinct advantage over the current standard of care treatments including potency, efficacy, and extended treatment window.

Topics: Administration, Oral; Animals; Antiviral Agents; Aza Compounds; Biological Availability; Dogs; Drug Resistance, Viral; Indoles; Influenza A virus; Madin Darby Canine Kidney Cells; Male; Mice, Inbred BALB C; Models, Molecular; Molecular Structure; Orthomyxoviridae Infections; Rats; RNA-Dependent RNA Polymerase; Species Specificity; Stereoisomerism; Structure-Activity Relationship; Viral Proteins; Virus Replication