rupintrivir and pleconaril

The common cold is an important illness both as a result of the economic impact of this common disease and because of the morbidity associated with the complications of the illness. Recent attempts to develop antiviral treatments for the common cold represent a substantial advance over previous efforts. Formidable barriers remain to be overcome, however, before any of these new products will be proven to be clinically useful. Recent advances in our understanding of the pathogenesis of common cold symptoms have provided insights into potential new targets for the treatment of this illness.

Topics: 3C Viral Proteases; Antiviral Agents; Clinical Trials as Topic; Combined Modality Therapy; Common Cold; Cysteine Endopeptidases; Dietary Supplements; Drug Therapy, Combination; Echinacea; Enzyme Inhibitors; Histamine H1 Antagonists; Humans; Intercellular Adhesion Molecule-1; Isoxazoles; Oxadiazoles; Oxazoles; Phenylalanine; Phytotherapy; Picornaviridae Infections; Plant Extracts; Plants, Medicinal; Pyrrolidinones; Receptors, Virus; Rhinovirus; Valine; Viral Proteins; Zinc

We describe the development, optimisation, and validation of an automated, cell-based and high-throughput screening assay using existing luminescence-based ATPlite reagents for identifying antiviral compounds that inhibit enterovirus replication. Antiviral efficacy was determined by measuring the ATP levels in cells that were protected from the viral cytopathic effect (CPE) by the antiviral compounds pleconaril and rupintrivir. CPE-based assay conditions were optimised at a cell density of 5000 cells/well and a viral infection dose of 100 CCID

Topics: Animals; Antiviral Agents; Chlorocebus aethiops; Cytopathogenic Effect, Viral; Enterovirus; Enterovirus Infections; HeLa Cells; Humans; Isoxazoles; Luminescent Measurements; Microbial Sensitivity Tests; Oxadiazoles; Oxazoles; Phenylalanine; Pyrrolidinones; Valine; Vero Cells

Human rhinovirus type C (HRV-C) is a newly discovered enterovirus species frequently associated with exacerbation of asthma and other acute respiratory conditions. Until recently, HRV-C could not be propagated in vitro, hampering in-depth characterization of the virus replication cycle and preventing efficient testing of antiviral agents. Herein we describe several subgenomic RNA replicon systems and a cell culture infectious model for HRV-C that can be used for antiviral screening. The replicon constructs consist of genome sequences from HRVc15, HRVc11, HRVc24, and HRVc25 strains, with the P1 capsid region replaced by a Renilla luciferase coding sequence. Following transfection of the replicon RNA into HeLa cells, the constructs produced time-dependent increases in luciferase signal that can be inhibited in a dose-dependent manner by known inhibitors of HRV replication, including the 3C protease inhibitor rupintrivir, the nucleoside analog inhibitor MK-0608, and the phosphatidylinositol 4-kinase IIIβ (PI4K-IIIβ) kinase inhibitor PIK93. Furthermore, with the exception of pleconaril and pirodavir, the other tested classes of HRV inhibitors blocked the replication of full-length HRVc15 and HRVc11 in human airway epithelial cells (HAEs) that were differentiated in the air-liquid interface, exhibiting antiviral activities similar to those observed with HRV-16. In summary, this study is the first comprehensive profiling of multiple classes of antivirals against HRV-C, and the set of newly developed quantitative HRV-C antiviral assays represent indispensable tools for the identification and evaluation of novel panserotype HRV inhibitors.

Topics: Antiviral Agents; Common Cold; Dose-Response Relationship, Drug; HeLa Cells; Humans; In Vitro Techniques; Isoxazoles; Oxadiazoles; Oxazoles; Phenylalanine; Piperidines; Pyridazines; Pyrrolidinones; Replicon; Rhinovirus; RNA, Viral; Tubercidin; Valine; Virus Replication

We tested the in vitro activity of pleconaril and AG7088 against five numbered human rhinovirus (HRV) serotypes and 46 clinical HRV isolates of undefined serotype recovered from patients with common colds. Antiviral effect of pleconaril and AG7088 were assessed by cytophathic effect (CPE) inhibition assays in Ohio HeLaI cells using microscopic and spectrophotometric methods. Both compounds were tested at concentrations of 1.0, 0.1 and 0.01 microg/ml. For the numbered HRV serotypes, the median EC(50) value determined by the microscopic CPE inhibition was slightly better for AG7088 compared to pleconaril (P=0.02) but was similar by spectrophotometric assay (P=0.15). For clinical HRV isolates the median EC(50) value determined microscopically was 0.01 microg/ml range, <0.01-0.04 microg/ml) for AG7088 compared to 0.07 microg/ml (range, <0.01->1 microg/ml) for pleconaril (P<0.001). The median EC(50) value determined by spectrophotometric assay was 0.01 microg/ml (range, <0.01-0.04 microg/ml) for AG7088 compared to 0.04 microg/ml (range, <0.01->1 microg/ml) for pleconaril (P<0.001). By either the microscopic or spectrophotometric methods the median EC(50) value of AG7088 was <1.0 microg/ml for all isolates and was >10.0 microg/ml of pleconaril for approximately 9% of isolates. In vitro AG7088 appeared to be more potent and to have a broader antirhinoviral spectrum than pleconaril among clinical HRV isolates. The clinical relevance of these in vitro results needs to be determined in controlled clinical trials.

Topics: Antiviral Agents; Cell Survival; Cells, Cultured; Common Cold; Humans; Isoxazoles; Oxadiazoles; Oxazoles; Phenylalanine; Pyrrolidinones; Reverse Transcriptase Polymerase Chain Reaction; Rhinovirus; Spectrophotometry; Valine