Cargando…
Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323
Arthropod-borne flavivirus infection continues to cause significant morbidity and mortality worldwide. Identification of drug targets and novel antiflaviviral compounds to treat these diseases has become a global health imperative. A previous screen of 235,456 commercially available small molecules...
Autores principales: | , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2015
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468182/ https://www.ncbi.nlm.nih.gov/pubmed/26075394 http://dx.doi.org/10.1371/journal.pone.0130083 |
_version_ | 1782376458032775168 |
---|---|
author | Bullard, Kristen M. Gullberg, Rebekah C. Soltani, Elnaz Steel, J. Jordan Geiss, Brian J. Keenan, Susan M. |
author_facet | Bullard, Kristen M. Gullberg, Rebekah C. Soltani, Elnaz Steel, J. Jordan Geiss, Brian J. Keenan, Susan M. |
author_sort | Bullard, Kristen M. |
collection | PubMed |
description | Arthropod-borne flavivirus infection continues to cause significant morbidity and mortality worldwide. Identification of drug targets and novel antiflaviviral compounds to treat these diseases has become a global health imperative. A previous screen of 235,456 commercially available small molecules identified the 2-thioxothiazolidin-4-one family of compounds as inhibitors of the flaviviral NS5 capping enzyme, a promising target for antiviral drug development. Rational drug design methodologies enabled identification of lead compound BG-323 from this series. We have shown previously that BG-323 potently inhibits NS5 capping enzyme activity, displays antiviral effects in dengue virus replicon assays and inhibits growth of West Nile and yellow fever viruses with low cytotoxicity in vitro. In this study we further characterized BG-323’s antiviral activity in vitro and in vivo. We found that BG-323 was able to reduce replication of WNV (NY99) and Powassan viruses in culture, and we were unable to force resistance into WNV (Kunjin) in long-term culture experiments. We then evaluated the antiviral activity of BG-323 in a murine model. Mice were challenged with WNV NY99 and administered BG-323 or mock by IP inoculation immediately post challenge and twice daily thereafter. Mice were bled and viremia was quantified on day three. No significant differences in viremia were observed between BG-323-treated and control groups and clinical scores indicated both BG-323-treated and control mice developed signs of illness on approximately the same day post challenge. To determine whether differences in in vitro and in vivo efficacy were due to unfavorable pharmacokinetic properties of BG-323, we conducted a pharmacokinetic evaluation of this small molecule. Insights from pharmacokinetic studies indicate that BG-323 is cell permeable, has a low efflux ratio and does not significantly inhibit two common cytochrome P450 (CYP P450) isoforms thus suggesting this molecule may be less likely to cause adverse drug interactions. However, the T(1/2) of BG-323 was suboptimal and the percent of drug bound to plasma binding proteins was high. Future studies with BG-323 will be aimed at increasing the T(1/2) and determining strategies for mitigating the effects of high plasma protein binding, which likely contribute to low in vivo efficacy. |
format | Online Article Text |
id | pubmed-4468182 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-44681822015-06-25 Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 Bullard, Kristen M. Gullberg, Rebekah C. Soltani, Elnaz Steel, J. Jordan Geiss, Brian J. Keenan, Susan M. PLoS One Research Article Arthropod-borne flavivirus infection continues to cause significant morbidity and mortality worldwide. Identification of drug targets and novel antiflaviviral compounds to treat these diseases has become a global health imperative. A previous screen of 235,456 commercially available small molecules identified the 2-thioxothiazolidin-4-one family of compounds as inhibitors of the flaviviral NS5 capping enzyme, a promising target for antiviral drug development. Rational drug design methodologies enabled identification of lead compound BG-323 from this series. We have shown previously that BG-323 potently inhibits NS5 capping enzyme activity, displays antiviral effects in dengue virus replicon assays and inhibits growth of West Nile and yellow fever viruses with low cytotoxicity in vitro. In this study we further characterized BG-323’s antiviral activity in vitro and in vivo. We found that BG-323 was able to reduce replication of WNV (NY99) and Powassan viruses in culture, and we were unable to force resistance into WNV (Kunjin) in long-term culture experiments. We then evaluated the antiviral activity of BG-323 in a murine model. Mice were challenged with WNV NY99 and administered BG-323 or mock by IP inoculation immediately post challenge and twice daily thereafter. Mice were bled and viremia was quantified on day three. No significant differences in viremia were observed between BG-323-treated and control groups and clinical scores indicated both BG-323-treated and control mice developed signs of illness on approximately the same day post challenge. To determine whether differences in in vitro and in vivo efficacy were due to unfavorable pharmacokinetic properties of BG-323, we conducted a pharmacokinetic evaluation of this small molecule. Insights from pharmacokinetic studies indicate that BG-323 is cell permeable, has a low efflux ratio and does not significantly inhibit two common cytochrome P450 (CYP P450) isoforms thus suggesting this molecule may be less likely to cause adverse drug interactions. However, the T(1/2) of BG-323 was suboptimal and the percent of drug bound to plasma binding proteins was high. Future studies with BG-323 will be aimed at increasing the T(1/2) and determining strategies for mitigating the effects of high plasma protein binding, which likely contribute to low in vivo efficacy. Public Library of Science 2015-06-15 /pmc/articles/PMC4468182/ /pubmed/26075394 http://dx.doi.org/10.1371/journal.pone.0130083 Text en © 2015 Bullard et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Bullard, Kristen M. Gullberg, Rebekah C. Soltani, Elnaz Steel, J. Jordan Geiss, Brian J. Keenan, Susan M. Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title | Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title_full | Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title_fullStr | Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title_full_unstemmed | Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title_short | Murine Efficacy and Pharmacokinetic Evaluation of the Flaviviral NS5 Capping Enzyme 2-Thioxothiazolidin-4-One Inhibitor BG-323 |
title_sort | murine efficacy and pharmacokinetic evaluation of the flaviviral ns5 capping enzyme 2-thioxothiazolidin-4-one inhibitor bg-323 |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468182/ https://www.ncbi.nlm.nih.gov/pubmed/26075394 http://dx.doi.org/10.1371/journal.pone.0130083 |
work_keys_str_mv | AT bullardkristenm murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 AT gullbergrebekahc murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 AT soltanielnaz murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 AT steeljjordan murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 AT geissbrianj murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 AT keenansusanm murineefficacyandpharmacokineticevaluationoftheflaviviralns5cappingenzyme2thioxothiazolidin4oneinhibitorbg323 |