Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.

<h4>Background</h4>The HIV-1 maturation inhibitor, 3-O-(3',3'-dimethylsuccinyl) betulinic acid (bevirimat, PA-457) is a promising drug candidate with 10 nM in vitro antiviral activity against multiple wild-type (WT) and drug-resistant HIV-1 isolates. Bevirimat has a novel mecha...

Full description

Saved in:
Bibliographic Details
Main Authors: Cheryl A Stoddart, Pheroze Joshi, Barbara Sloan, Jennifer C Bare, Philip C Smith, Graham P Allaway, Carl T Wild, David E Martin
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2007-11-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0001251&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850240308009238528
author Cheryl A Stoddart
Pheroze Joshi
Barbara Sloan
Jennifer C Bare
Philip C Smith
Graham P Allaway
Carl T Wild
David E Martin
author_facet Cheryl A Stoddart
Pheroze Joshi
Barbara Sloan
Jennifer C Bare
Philip C Smith
Graham P Allaway
Carl T Wild
David E Martin
author_sort Cheryl A Stoddart
collection DOAJ
description <h4>Background</h4>The HIV-1 maturation inhibitor, 3-O-(3',3'-dimethylsuccinyl) betulinic acid (bevirimat, PA-457) is a promising drug candidate with 10 nM in vitro antiviral activity against multiple wild-type (WT) and drug-resistant HIV-1 isolates. Bevirimat has a novel mechanism of action, specifically inhibiting cleavage of spacer peptide 1 (SP1) from the C-terminus of capsid which results in defective core condensation.<h4>Methods and findings</h4>Oral administration of bevirimat to HIV-1-infected SCID-hu Thy/Liv mice reduced viral RNA by >2 log(10) and protected immature and mature T cells from virus-mediated depletion. This activity was observed at plasma concentrations that are achievable in humans after oral dosing, and bevirimat was active up to 3 days after inoculation with both WT HIV-1 and an AZT-resistant HIV-1 clinical isolate. Consistent with its mechanism of action, bevirimat caused a dose-dependent inhibition of capsid-SP1 cleavage in HIV-1-infected human thymocytes obtained from these mice. HIV-1 NL4-3 with an alanine-to-valine substitution at the N-terminus of SP1 (SP1/A1V), which is resistant to bevirimat in vitro, was also resistant to bevirimat treatment in the mice, and SP1/AIV had replication and thymocyte kinetics similar to that of WT NL4-3 with no evidence of fitness impairment in in vivo competition assays. Interestingly, protease inhibitor-resistant HIV-1 with impaired capsid-SP1 cleavage was hypersensitive to bevirimat in vitro with a 50% inhibitory concentration 140 times lower than for WT HIV-1.<h4>Conclusions</h4>These results support further clinical development of this first-in-class maturation inhibitor and confirm the usefulness of the SCID-hu Thy/Liv model for evaluation of in vivo antiretroviral efficacy, drug resistance, and viral fitness.
format Article
id doaj-art-767cee83f8bd4f77a00802dac5c2710b
institution OA Journals
issn 1932-6203
language English
publishDate 2007-11-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-767cee83f8bd4f77a00802dac5c2710b2025-08-20T02:00:54ZengPublic Library of Science (PLoS)PLoS ONE1932-62032007-11-01211e125110.1371/journal.pone.0001251Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.Cheryl A StoddartPheroze JoshiBarbara SloanJennifer C BarePhilip C SmithGraham P AllawayCarl T WildDavid E Martin<h4>Background</h4>The HIV-1 maturation inhibitor, 3-O-(3',3'-dimethylsuccinyl) betulinic acid (bevirimat, PA-457) is a promising drug candidate with 10 nM in vitro antiviral activity against multiple wild-type (WT) and drug-resistant HIV-1 isolates. Bevirimat has a novel mechanism of action, specifically inhibiting cleavage of spacer peptide 1 (SP1) from the C-terminus of capsid which results in defective core condensation.<h4>Methods and findings</h4>Oral administration of bevirimat to HIV-1-infected SCID-hu Thy/Liv mice reduced viral RNA by >2 log(10) and protected immature and mature T cells from virus-mediated depletion. This activity was observed at plasma concentrations that are achievable in humans after oral dosing, and bevirimat was active up to 3 days after inoculation with both WT HIV-1 and an AZT-resistant HIV-1 clinical isolate. Consistent with its mechanism of action, bevirimat caused a dose-dependent inhibition of capsid-SP1 cleavage in HIV-1-infected human thymocytes obtained from these mice. HIV-1 NL4-3 with an alanine-to-valine substitution at the N-terminus of SP1 (SP1/A1V), which is resistant to bevirimat in vitro, was also resistant to bevirimat treatment in the mice, and SP1/AIV had replication and thymocyte kinetics similar to that of WT NL4-3 with no evidence of fitness impairment in in vivo competition assays. Interestingly, protease inhibitor-resistant HIV-1 with impaired capsid-SP1 cleavage was hypersensitive to bevirimat in vitro with a 50% inhibitory concentration 140 times lower than for WT HIV-1.<h4>Conclusions</h4>These results support further clinical development of this first-in-class maturation inhibitor and confirm the usefulness of the SCID-hu Thy/Liv model for evaluation of in vivo antiretroviral efficacy, drug resistance, and viral fitness.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0001251&type=printable
spellingShingle Cheryl A Stoddart
Pheroze Joshi
Barbara Sloan
Jennifer C Bare
Philip C Smith
Graham P Allaway
Carl T Wild
David E Martin
Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
PLoS ONE
title Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
title_full Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
title_fullStr Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
title_full_unstemmed Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
title_short Potent activity of the HIV-1 maturation inhibitor bevirimat in SCID-hu Thy/Liv mice.
title_sort potent activity of the hiv 1 maturation inhibitor bevirimat in scid hu thy liv mice
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0001251&type=printable
work_keys_str_mv AT cherylastoddart potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT pherozejoshi potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT barbarasloan potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT jennifercbare potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT philipcsmith potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT grahampallaway potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT carltwild potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice
AT davidemartin potentactivityofthehiv1maturationinhibitorbevirimatinscidhuthylivmice