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de Vries M, Bonsmann S, Pausch J, Sumner M, Birkmann A, Zimmermann H, Kropeit D. Evaluation of the Clinical Drug-Drug Interaction Potential of Pritelivir on Transporters and CYP450 Enzymes Using a Cocktail Approach. Clin Pharmacol Drug Dev 2024; 13:755-769. [PMID: 38752475 DOI: 10.1002/cpdd.1408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 04/08/2024] [Indexed: 07/05/2024]
Abstract
Pritelivir is a novel viral helicase-primase inhibitor active against herpes simplex virus. In vitro drug-drug interaction studies indicated that pritelivir has the potential for clinically relevant interactions on the cytochrome P450 (CYP) enzymes 2C8, 2C9, 3A4, and 2B6, and intestinal uptake transporter organic anion transporting polypeptide (OATP) 2B1 and efflux transporter breast cancer resistance protein (BCRP). This was evaluated in 2 clinical trials. In 1 trial the substrates flurbiprofen (CYP2C9), bupropion (CYP2B6), and midazolam (CYP3A4) were administered simultaneously as part of the Geneva cocktail, while the substrate celiprolol (OAPT2B1) was administered separately. In another trial, the substrates repaglinide (CYP2C8) and rosuvastatin (BCRP) were administered separately. Exposure parameters of the substrates and their metabolites (flurbiprofen and bupropion only) were compared after administration with or without pritelivir under therapeutic concentrations. The results of these trials indicated that pritelivir has no clinically relevant effect on the exposure of substrates for the intestinal uptake transporter OATP2B1 and the CYP enzymes 3A4, 2B6, 2C9, and 2C8, and has a weak inhibitory effect on the intestinal efflux transporter BCRP. In summary, the results suggest that pritelivir has a low drug-drug interaction potential.
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Affiliation(s)
| | | | - Jörg Pausch
- AiCuris Anti-infective Cures AG, Wuppertal, Germany
- Present affiliation: BioNTech SE, Mainz, Germany
| | | | | | | | - Dirk Kropeit
- AiCuris Anti-infective Cures AG, Wuppertal, Germany
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2
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Bernstein DI, Sawtell NM, Bravo FJ, Dixon DA, Gege C, Kleymann G. Intermittent therapy with helicase-primase inhibitor IM-250 efficiently controls recurrent herpes disease and reduces reactivation of latent HSV. Antiviral Res 2023; 219:105733. [PMID: 37858763 DOI: 10.1016/j.antiviral.2023.105733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 10/21/2023]
Abstract
Herpes is a contagious life-long infection with persistently high incidence and prevalence, causing significant disease worldwide. Current therapies have efficacy against active HSV infections but no impact on the latent viral reservoir in neurons. Thus, despite treatment, disease recurs from latency and the infectious potential remains unaffected within patients. Here, efficacy of the helicase-primase inhibitor (HPI) IM-250 against chronic neuronal HSV infections utilizing two classic herpes in vivo latency/reactivation animal models (intravaginal guinea pig HSV-2 infection model and ocular mouse HSV-1 infection model) is presented. Intermittent therapy of infected animals with 4-7 cycles of IM-250 during latency silences subsequent recurrences analyzed up to 6 months. In contrast to common experience, our studies show that the latent reservoir is indeed accessible to antiviral therapy altering the latent viral reservoir such that reactivation frequency can be reduced significantly by prior IM-250 treatment. We provide evidence that antiviral treatment during HSV latency can reduce future reactivation from the latent reservoir, supporting a conceptual shift in the antiviral field, and reframing what is achievable with respect to therapy of latent neuronal HSV infections.
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Affiliation(s)
- David I Bernstein
- Cincinnati Children's Hospital Medical Center (CCHMC), University of Cincinnati, OH, USA
| | - Nancy M Sawtell
- Cincinnati Children's Hospital Medical Center (CCHMC), University of Cincinnati, OH, USA
| | - Fernando J Bravo
- Cincinnati Children's Hospital Medical Center (CCHMC), University of Cincinnati, OH, USA
| | - David A Dixon
- Cincinnati Children's Hospital Medical Center (CCHMC), University of Cincinnati, OH, USA
| | - Christian Gege
- Innovative Molecules GmbH, Lipowsky Str. 10, 81373, Munich, Bavaria, Germany
| | - Gerald Kleymann
- Innovative Molecules GmbH, Lipowsky Str. 10, 81373, Munich, Bavaria, Germany.
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3
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Kropeit D, Bonsmann S, von Richter O, McCormick D, Pausch J, Sumner M, Birkmann A, Zimmermann H, Rübsamen-Schaeff H. First-in-Human, Single- and Multiple-Ascending-Dose, Food-Effect, and Absolute Bioavailability Trials to Assess the Pharmacokinetics, Safety, and Tolerability of Pritelivir, a Nonnucleoside Helicase-Primase Inhibitor Against Herpes Simplex Virus in Healthy Subjects. Clin Pharmacol Drug Dev 2023; 12:749-760. [PMID: 36860173 DOI: 10.1002/cpdd.1241] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/03/2023] [Indexed: 03/03/2023]
Abstract
The pharmacokinetics and safety of the novel herpes simplex virus helicase-primase inhibitor pritelivir were evaluated in 5 phase 1 trials: a single-ascending-dose trial, 2 multiple-ascending-dose trials, a food-effect trial, and an absolute bioavailability trial in healthy male subjects. One cohort of healthy female subjects was included in the single-ascending-dose trial. Pritelivir pharmacokinetics were linear up to 480 mg following single and up to 400 mg following multiple once-daily doses. The half-life ranged from 52 to 83 hours, and steady state was reached between 8 and 13 days. Maximum plasma concentration and area under the plasma concentration-time curve from time 0 to the last quantifiable concentration were 1.5- and 1.1-fold higher in female compared to male subjects. Absolute bioavailability was 72% under fasted conditions. Following a fatty diet, pritelivir time to maximum concentration was 1.5 hour delayed and maximum plasma concentration and area under the plasma concentration-time curve from time 0 to the last quantifiable concentration were 33% and 16% higher, respectively. Pritelivir was safe and well tolerated up to 600 mg following single and up to 200 mg following multiple once-daily doses. Considering a therapeutic dose of 100 mg once-daily, pritelivir demonstrated a favorable safety and tolerability and pharmacokinetic profile in healthy subjects to support further development.
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Affiliation(s)
- Dirk Kropeit
- Aicuris Anti-infective Cures AG, Wuppertal, Germany
| | | | - Oliver von Richter
- Global Clinical Development, Biopharmaceuticals, Hexal AG (A Sandoz Company), Holzkirchen, Germany
| | - David McCormick
- Aicuris Anti-infective Cures AG (Retired), Wuppertal, Germany
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4
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Bosetti D, Bernardi C, Maulini M, Giannotti F, Mamez AC, Masouridi-Levrat S, Chalandon Y, Neofytos D. Salvage Treatment of Refractory HSV Oral Lesions with Pritelivir in Allogeneic Hematopoietic Cell Transplant Recipients. Antimicrob Agents Chemother 2023; 67:e0173222. [PMID: 36971558 PMCID: PMC10112206 DOI: 10.1128/aac.01732-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 02/03/2023] [Indexed: 03/29/2023] Open
Abstract
We present two allogeneic hematopoietic cell transplantation recipients (HCTr) treated with pritelivir for acyclovir-resistant/refractory (r/r) HSV infection based on the expanded access program of the pritelivir manufacturer. Outpatient treatment with pritelivir was administered, with partial response by week 1 of treatment and complete response by week 4 of treatment in both patients. No adverse events were noted. Pritelivir appears to be an effective and safe option for the management of acyclovir-r/r HSV infections in highly immunocompromised patients in an outpatient setting.
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Affiliation(s)
- Davide Bosetti
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Chiara Bernardi
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Marie Maulini
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Federica Giannotti
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Anne-Claire Mamez
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Stavroula Masouridi-Levrat
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Yves Chalandon
- Division of Hematology, Bone Marrow Transplant Unit, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Dionysios Neofytos
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
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5
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Birkmann A, Bonsmann S, Kropeit D, Pfaff T, Rangaraju M, Sumner M, Timmler B, Zimmermann H, Buschmann H, Ruebsamen-Schaeff H. Discovery, Chemistry, and Preclinical Development of Pritelivir, a Novel Treatment Option for Acyclovir-Resistant Herpes Simplex Virus Infections. J Med Chem 2022; 65:13614-13628. [PMID: 36202389 PMCID: PMC9620171 DOI: 10.1021/acs.jmedchem.2c00668] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
When the nucleoside analogue acyclovir was introduced
in the early
1980s, it presented a game-changing treatment modality for herpes
simplex virus infections. Since then, work has been ongoing to improve
the weaknesses that have now been identified: a narrow time window
for therapeutic success, resistance in immunocompromised patients,
little influence on frequency of recurrences, relatively fast elimination,
and poor bioavailability. The present Drug Annotation focuses on the
helicase–primase inhibitor pritelivir currently in development
for the treatment of acyclovir-resistant HSV infections and describes
how a change of the molecular target (from viral DNA polymerase to
the HSV helicase–primase complex) afforded improvement of the
shortcomings of nucleoside analogs. Details are presented for the
discovery process leading to the final drug candidate, the pivotal
preclinical studies on mechanism of action and efficacy, and on how
ongoing clinical research has been able to translate preclinical promises
into clinical use.
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Affiliation(s)
| | | | - Dirk Kropeit
- AiCuris Anti-Infective Cures AG, 42117 Wuppertal, Germany
| | - Tamara Pfaff
- AiCuris Anti-Infective Cures AG, 42117 Wuppertal, Germany
| | | | - Melanie Sumner
- AiCuris Anti-Infective Cures AG, 42117 Wuppertal, Germany
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Bermek O, Williams RS. The three-component helicase/primase complex of herpes simplex virus-1. Open Biol 2021; 11:210011. [PMID: 34102080 PMCID: PMC8187027 DOI: 10.1098/rsob.210011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) is one of the nine herpesviruses that infect humans. HSV-1 encodes seven proteins to replicate its genome in the hijacked human cell. Among these are the herpes virus DNA helicase and primase that are essential components of its replication machinery. In the HSV-1 replisome, the helicase-primase complex is composed of three components including UL5 (helicase), UL52 (primase) and UL8 (non-catalytic subunit). UL5 and UL52 subunits are functionally interdependent, and the UL8 component is required for the coordination of UL5 and UL52 activities proceeding in opposite directions with respect to the viral replication fork. Anti-viral compounds currently under development target the functions of UL5 and UL52. Here, we review the structural and functional properties of the UL5/UL8/UL52 complex and highlight the gaps in knowledge to be filled to facilitate molecular characterization of the structure and function of the helicase-primase complex for development of alternative anti-viral treatments.
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Affiliation(s)
- Oya Bermek
- Genome Integrity and Structural Biology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - R Scott Williams
- Genome Integrity and Structural Biology Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
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7
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Zhdanova KA, Savelyeva IO, Ezhov AV, Zhdanov AP, Zhizhin KY, Mironov AF, Bragina NA, Babayants AA, Frolova IS, Filippova NI, Scliankina NN, Scheglovitova ON. Novel Cationic Meso-Arylporphyrins and Their Antiviral Activity against HSV-1. Pharmaceuticals (Basel) 2021; 14:ph14030242. [PMID: 33800457 PMCID: PMC7999199 DOI: 10.3390/ph14030242] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 02/07/2023] Open
Abstract
This work is devoted to the search for new antiherpes simplex virus type 1 (HSV-1) drugs among synthetic tetrapyrroles and to an investigation of their antiviral properties under nonphotodynamic conditions. In this study, novel amphiphilic 5,10,15,20-tetrakis(4-(3-pyridyl-n-propanoyl)oxyphenyl)porphyrin tetrabromide (3a), 5,10,15,20-tetrakis(4-(6-pyridyl-n-hexanoyl)oxyphenyl)porphyrin tetrabromide (3b) and known 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetraiodide (TMePyP) were synthesized, and their dark antiviral activity in vitro against HSV-1 was studied. The influence of porphyrin’s nanosized delivery vehicles based on Pluronic F127 on anti-HSV-1 activity was estimated. All the received compounds 3a, 3b and TMePyP showed virucidal efficiency and had an effect on viral replication stages. The new compound 3b showed the highest antiviral activity, close to 100%, with the lowest concentration, while the maximum TMePyP activity was observed with a high concentration; porphyrin 3a was the least active. The inclusion of the synthesized compounds in Pluronic F-127 polymeric micelles had a noticeable effect on antiviral activity only at higher porphyrin concentrations. Action of the received compounds differs by influence on the early or later reproduction stages. While 3a and TMePyP acted on all stages of the viral replication cycle, porphyrin 3b inhibited viral replication during the early stages of infection. The resulting compounds are promising for the development of utilitarian antiviral agents and, possibly, medical antiviral drugs.
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Affiliation(s)
- Kseniya A. Zhdanova
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
- Correspondence: ; Tel.: +79-261-126-692
| | - Inga O. Savelyeva
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
| | - Artem V. Ezhov
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
| | - Andrey P. Zhdanov
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Leninskii Pr. 31, Moscow 117907, Russia;
| | - Konstantin Yu. Zhizhin
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Leninskii Pr. 31, Moscow 117907, Russia;
| | - Andrey F. Mironov
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
| | - Natal’ya A. Bragina
- MIREA—Russian Technological University, Vernadsky Prospect 86, Moscow 119571, Russia; (I.O.S.); (A.V.E.); (K.Y.Z.); (A.F.M.); (N.A.B.)
| | - Alla A. Babayants
- Gamaleya Research Center of Epidemiology and Microbiology, Gamaleya Str. 18, Moscow 123098, Russia; (A.A.B.); (I.S.F.); (N.I.F.); (N.N.S.); (O.N.S.)
| | - Irina S. Frolova
- Gamaleya Research Center of Epidemiology and Microbiology, Gamaleya Str. 18, Moscow 123098, Russia; (A.A.B.); (I.S.F.); (N.I.F.); (N.N.S.); (O.N.S.)
| | - Nadezhda I. Filippova
- Gamaleya Research Center of Epidemiology and Microbiology, Gamaleya Str. 18, Moscow 123098, Russia; (A.A.B.); (I.S.F.); (N.I.F.); (N.N.S.); (O.N.S.)
| | - Nadezhda N. Scliankina
- Gamaleya Research Center of Epidemiology and Microbiology, Gamaleya Str. 18, Moscow 123098, Russia; (A.A.B.); (I.S.F.); (N.I.F.); (N.N.S.); (O.N.S.)
| | - Olga N. Scheglovitova
- Gamaleya Research Center of Epidemiology and Microbiology, Gamaleya Str. 18, Moscow 123098, Russia; (A.A.B.); (I.S.F.); (N.I.F.); (N.N.S.); (O.N.S.)
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8
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Bernstein DI. Use of the Guinea pig model of genital herpes to evaluate vaccines and antivirals: Review. Antiviral Res 2020; 180:104821. [PMID: 32544409 PMCID: PMC10713199 DOI: 10.1016/j.antiviral.2020.104821] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/06/2020] [Accepted: 05/12/2020] [Indexed: 12/23/2022]
Abstract
Herpes simplex virus (HSV) infections type 1 (HSV-1) and type 2 (HSV-2) are common throughout the world. Infections are lifelong and may produce both acute and recurrent vesiculoulcerative disease as well as more severe diseases. Despite disappointing results from recent HSV vaccine trials new vaccines and more potent antiviral therapies continue to be developed. These newer approaches require initial evaluations in animal models. In this review I have briefly described some of the models available and then more thoroughly describe the guinea pig model of acute and recurrent genital herpes infections. As discussed, the guinea pig model most closely mimics human disease and provides several important endpoints for evaluating vaccines and antivirals.
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Affiliation(s)
- David I Bernstein
- University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
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9
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Iqbal UH, Zeng E, Pasinetti GM. The Use of Antimicrobial and Antiviral Drugs in Alzheimer's Disease. Int J Mol Sci 2020; 21:E4920. [PMID: 32664669 PMCID: PMC7404195 DOI: 10.3390/ijms21144920] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 12/15/2022] Open
Abstract
The aggregation and accumulation of amyloid-β plaques and tau proteins in the brain have been central characteristics in the pathophysiology of Alzheimer's disease (AD), making them the focus of most of the research exploring potential therapeutics for this neurodegenerative disease. With success in interventions aimed at depleting amyloid-β peptides being limited at best, a greater understanding of the physiological role of amyloid-β peptides is needed. The development of amyloid-β plaques has been determined to occur 10-20 years prior to AD symptom manifestation, hence earlier interventions might be necessary to address presymptomatic AD. Furthermore, recent studies have suggested that amyloid-β peptides may play a role in innate immunity as an antimicrobial peptide. These findings, coupled with the evidence of pathogens such as viruses and bacteria in AD brains, suggests that the buildup of amyloid-β plaques could be a response to the presence of viruses and bacteria. This has led to the foundation of the antimicrobial hypothesis for AD. The present review will highlight the current understanding of amyloid-β, and the role of bacteria and viruses in AD, and will also explore the therapeutic potential of antimicrobial and antiviral drugs in Alzheimer's disease.
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Affiliation(s)
| | | | - Giulio M. Pasinetti
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (U.H.I.); (E.Z.)
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10
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Inactivated Orf-virus shows disease modifying antiviral activity in a guinea pig model of genital herpesvirus infection. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2017; 51:587-592. [PMID: 28711432 DOI: 10.1016/j.jmii.2017.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 01/24/2017] [Accepted: 03/13/2017] [Indexed: 11/21/2022]
Abstract
BACKGROUND Inactivated Orf virus (iORFV) has been used as a preventative as well as a therapeutic immunomodulator in veterinary medicine in different species. iORFV elicits strong effects on cytokine secretion in mice and human immune cells leading to an auto-regulated loop of initial up-regulation of inflammatory and Th1-related cytokines followed by Th2-related cytokines that attenuate immunopathology. The therapeutic potential of iORFV has been recognized in several models for difficult-to-treat disease areas such as chronic viral diseases, liver fibrosis or various forms of cancer. METHODS Guinea pigs were infected with Human Herpesvirus (HSV)-2 strain MS and treated with iORFV, Acyclovir (ACV) or placebo, respectively. Clinical score of herpes lesions and viral shedding was assessed over a period of 40 days. In addition, viral DNA in dorsal root ganglia was quantified at the end of the study. RESULTS Disease symptoms were minimal or absent in iORFV-treated guinea pigs but tended to be severe in animals treated with either ACV or placebo. The cumulated disease score was significantly reduced in iORFV-treated but not in ACV- or placebo-treated guinea pigs. In addition, treatment with iORFV, but not ACV or placebo, led to significant reduction of viral DNA load in dorsal root ganglia. CONCLUSION iORFV effectively suppressed recurrences in guinea pigs experimentally infected with HSV. iORFV did not only reduce recurrent disease episodes but was, compared with ACV, more effective in reducing latency as measured by viral DNA detected in dorsal root ganglia of infected animals.
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Abstract
Herpes simplex virus (HSV), a member of the Herpesviridae family, is a significant human pathogen that results in mucocutaneous lesions in the oral cavity or genital infections. Acyclovir (ACV) and related nucleoside analogues can successfully treat HSV infections, but the emergence of drug resistance to ACV has created a barrier for the treatment of HSV infections, especially in immunocompromised patients. There is an urgent need to explore new and effective tactics to circumvent drug resistance to HSV. This review summarises the current strategies in the development of new targets (the DNA helicase/primase (H/P) complex), new types of molecules (nature products) and new antiviral mechanisms (lethal mutagenesis of Janus-type nucleosides) to fight the drug resistance of HSV.
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12
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Collot M, Rouard C, Brunet C, Agut H, Boutolleau D, Burrel S. High conservation of herpes simplex virus UL5/UL52 helicase-primase complex in the era of new antiviral therapies. Antiviral Res 2016; 128:1-6. [PMID: 26826441 DOI: 10.1016/j.antiviral.2016.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 01/13/2016] [Accepted: 01/22/2016] [Indexed: 10/22/2022]
Abstract
The emergence of herpes simplex virus (HSV) resistance to current antiviral drugs, that all target the viral DNA polymerase, constitutes a major obstacle to antiviral treatment effectiveness of HSV infections, especially in immunocompromised patients. A novel and promising class of inhibitors of the HSV UL5/UL52 helicase-primase (HP) complex has been reported to hinder viral replication with a high potency. In this study, we describe the low natural polymorphism (interstrain identity >99.1% at both nucleotide and amino acid levels) of HSV HP complex subunits pUL5 and pUL52 among 64 HSV (32 HSV-1 and 32 HSV-2) clinical isolates, and we show that the HSV resistance profile to the first-line antiviral drug acyclovir (ACV) does not impact on the natural polymorphism of HSV HP complex. Genotypic tools and polymorphism data concerning HSV HP complex provided herein will be useful to detect drug resistance mutations in a relevant time frame when HP inhibitors (HPIs), i.e., amenamevir and pritelivir, will be available in medical practice.
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Affiliation(s)
- Marianne Collot
- Centre Hospitalier et Universitaire de Nantes, Service de Virologie, Nantes, France; EA4271 « Immunovirology and Genetic Polymorphism », Université de Nantes, France
| | - Caroline Rouard
- AP-HP, Hôpital Universitaire Antoine Béclère, Service de Microbiologie, Clamart, France; EA4043 - Unité Bactéries Pathogènes et Santé UFR de Pharmacie-Université Paris-Sud, France
| | - Christel Brunet
- AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, Service de Virologie, Paris, France
| | - Henri Agut
- AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, Service de Virologie, Paris, France; Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), INSERM U1135, Paris, France
| | - David Boutolleau
- AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, Service de Virologie, Paris, France; Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), INSERM U1135, Paris, France
| | - Sonia Burrel
- AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, Service de Virologie, Paris, France; Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), INSERM U1135, Paris, France.
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13
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Sweeney NL, Hanson AM, Mukherjee S, Ndjomou J, Geiss BJ, Steel JJ, Frankowski KJ, Li K, Schoenen FJ, Frick DN. Benzothiazole and Pyrrolone Flavivirus Inhibitors Targeting the Viral Helicase. ACS Infect Dis 2015; 1:140-148. [PMID: 26029739 DOI: 10.1021/id5000458] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The flavivirus nonstructural protein 3 (NS3) is a protease and helicase, and on the basis of its similarity to its homologue encoded by the hepatitis C virus (HCV), the flavivirus NS3 might be a promising drug target. Few flavivirus helicase inhibitors have been reported, in part, because few specific inhibitors have been identified when nucleic acid unwinding assays have been used to screen for helicase inhibitors. To explore the possibility that compounds inhibiting NS3-catalyzed ATP hydrolysis might function as antivirals even if they do not inhibit RNA unwinding in vitro, we designed a robust dengue virus (DENV) NS3 ATPase assay suitable for high-throughput screening. Members of two classes of inhibitory compounds were further tested in DENV helicase-catalyzed RNA unwinding assays, assays monitoring HCV helicase action, subgenomic DENV replicon assays, and cell viability assays and for their ability to inhibit West Nile virus (Kunjin subtype) replication in cells. The first class contained analogues of NIH molecular probe ML283, a benzothiazole oligomer derived from the dye primuline, and they also inhibited HCV helicase and DENV NS3-catalyzed RNA unwinding. The most intriguing ML283 analogue inhibited DENV NS3 with an IC50 value of 500 nM and was active against the DENV replicon. The second class contained specific DENV ATPase inhibitors that did not inhibit DENV RNA unwinding or reactions catalyzed by HCV helicase. Members of this class contained a 4-hydroxy-3-(5-methylfuran-2-carbonyl)-2H-pyrrol-5-one scaffold, and about 20 μM of the most potent pyrrolone inhibited both DENV replicons and West Nile virus replication in cells by 50%.
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Affiliation(s)
- Noreena L. Sweeney
- Department of Chemistry and Biochemistry, University of Wisconsin—Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Alicia M. Hanson
- Department of Chemistry and Biochemistry, University of Wisconsin—Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Sourav Mukherjee
- Department of Chemistry and Biochemistry, University of Wisconsin—Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Jean Ndjomou
- Department of Chemistry and Biochemistry, University of Wisconsin—Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Brian J. Geiss
- Department
of Microbiology, Immunology, and Pathology, 1682 Campus Delivery, Colorado State University, Fort Collins, Colorado 80523, United States
| | - J. Jordan Steel
- Department
of Microbiology, Immunology, and Pathology, 1682 Campus Delivery, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Kevin J. Frankowski
- Specialized
Chemistry Center, University of Kansas, 2034 Becker Drive, Lawrence, Kansas 66047, United States
| | - Kelin Li
- Specialized
Chemistry Center, University of Kansas, 2034 Becker Drive, Lawrence, Kansas 66047, United States
| | - Frank J. Schoenen
- Specialized
Chemistry Center, University of Kansas, 2034 Becker Drive, Lawrence, Kansas 66047, United States
| | - David N. Frick
- Department of Chemistry and Biochemistry, University of Wisconsin—Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States
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Kukhanova MK, Korovina AN, Kochetkov SN. Human herpes simplex virus: Life cycle and development of inhibitors. BIOCHEMISTRY (MOSCOW) 2015; 79:1635-52. [DOI: 10.1134/s0006297914130124] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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New Herpes Simplex Virus Replication Targets. Antiviral Res 2014. [DOI: 10.1128/9781555815493.ch20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Pharmacokinetics-pharmacodynamics of the helicase-primase inhibitor pritelivir following treatment of wild-type or pritelivir-resistant virus infection in a murine herpes simplex virus 1 infection model. Antimicrob Agents Chemother 2014; 58:3843-52. [PMID: 24752278 DOI: 10.1128/aac.02641-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Herpes simplex virus (HSV) infections can cause considerable morbidity. Transmission of HSV-2 has become a major health concern, since it has been shown to promote transmission of other sexually transmitted diseases. Pritelivir (AIC316, BAY 57-1293) belongs to a new class of HSV antiviral compounds, the helicase-primase inhibitors, which have a mode of action that is distinct from that of antiviral nucleoside analogues currently in clinical use. Analysis of pharmacokinetic-pharmacodynamic parameters is a useful tool for the selection of appropriate doses in clinical trials, especially for compounds belonging to new classes for which no or only limited data on therapeutic profiles are available. For this purpose, the effective dose of pritelivir was determined in a comprehensive mouse model of HSV infection. Corresponding plasma concentrations were measured, and exposures were compared with efficacious concentrations derived from cell cultures. The administration of pritelivir at 10 mg/kg of body weight once daily for 4 days completely suppressed any signs of HSV infection in the animals. Associated plasma concentrations adjusted for protein binding stayed above the cell culture 90% effective concentration (EC90) for HSV-1 for almost the entire dosing interval. Interestingly, by increasing the dose 6-fold and prolonging the treatment duration to 8 days, it was possible to treat mice infected with an approximately 30-fold pritelivir-resistant but fully pathogenic HSV-1 virus. Corresponding plasma concentrations exceeded the EC90 of this mutant for <8 h, indicating that even suboptimal exposure to pritelivir is sufficient to achieve antiviral efficacy, possibly augmented by other factors such as the immune system.
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Bernstein DI, Cardin RD, Bravo FJ, Earwood J, Clark JR, Li Y, Mishra P, Li C, Nayak BP, Miller AT, Wu TYH, Cooke MP, Valiante NM. Topical SMIP-7.7, a toll-like receptor 7 agonist, protects against genital herpes simplex virus type-2 disease in the guinea pig model of genital herpes. Antivir Chem Chemother 2014; 23:189-96. [PMID: 23232327 DOI: 10.3851/imp2499] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/15/2012] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Development of more effective therapies for genital herpes simplex virus type-2 (HSV-2) infections remains a priority. The toll-like receptors (TLR) are attractive targets for the immunomodulation of primary and recurrent genital herpes infection. The guinea pig model of genital HSV-2 disease was therefore used to evaluate the efficacy of a new TLR-7 agonist, SMIP-7.7. METHODS The effects of SMIP-7.7 at concentrations between 0.90% and 0.09% were compared to the vehicle control or Aldara(®) (3M Health Care Limited, Northridge, CA, USA) as treatment for genital HSV-2 infections. Following intravaginal inoculation of Hartley guinea pigs with 10(6) pfu HSV-2 (MS strain), animals were treated intravaginally beginning at 36 h post-infection. Animals were evaluated for acute disease, acute virus replication, recurrent disease and shedding, as well as infection of the dorsal root ganglia. RESULTS Treatment with SMIP-7.7 significantly decreased mean total lesion scores during primary infection (all doses, P<0.01 compared with vehicle control, and similar to Aldara(®)). Vaginal virus titres were reduced in treated animals compared with vehicle control (P<0.001 for each treatment versus vehicle control on day 4). Treatment with SMIP-7.7 also significantly decreased the number of recurrent lesion days, the number of days with recurrent virus shedding and the infection of the dorsal root ganglia compared to the vehicle control, and was similar to Aldara(®). As opposed to Aldara(®), SMIP-7.7 did not induce fever or weight loss during treatment. CONCLUSIONS SMIP-7.7 improves the outcome of primary and recurrent HSV-2 disease comparable to Aldara(®) but without some of the side effects associated with Aldara(®).
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Wald A, Corey L, Timmler B, Magaret A, Warren T, Tyring S, Johnston C, Kriesel J, Fife K, Galitz L, Stoelben S, Huang ML, Selke S, Stobernack HP, Ruebsamen-Schaeff H, Birkmann A. Helicase-primase inhibitor pritelivir for HSV-2 infection. N Engl J Med 2014; 370:201-10. [PMID: 24428466 DOI: 10.1056/nejmoa1301150] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pritelivir, an inhibitor of the viral helicase-primase complex, exhibits antiviral activity in vitro and in animal models of herpes simplex virus (HSV) infection. We tested the efficacy and safety of pritelivir in otherwise healthy persons with genital HSV-2 infection. METHODS We randomly assigned 156 HSV-2-positive persons with a history of genital herpes to receive one of four doses of oral pritelivir (5, 25, or 75 mg daily, or 400 mg weekly) or placebo for 28 days. Participants obtained daily swabs from the genital area for HSV-2 testing, which was performed with a polymerase-chain-reaction assay. Participants also maintained a diary of genital signs and symptoms. The primary end point was the rate of genital HSV shedding. RESULTS HSV shedding among placebo recipients was detected on 16.6% of days; shedding among pritelivir recipients was detected on 18.2% of days among those receiving 5 mg daily, 9.3% of days among those receiving 25 mg daily, 2.1% of days among those receiving 75 mg daily, and 5.3% of days among those receiving 400 mg weekly. The relative risk of viral shedding with pritelivir, as compared with placebo, was 1.11 (95% confidence interval [CI], 0.65 to 1.87) with the 5-mg daily dose, 0.57 (95% CI, 0.31 to 1.03) with the 25-mg daily dose, 0.13 (95% CI, 0.04 to 0.38) with the 75-mg daily dose, and 0.32 (95% CI, 0.17 to 0.59) with the 400-mg weekly dose. The percentage of days with genital lesions was also significantly reduced, from 9.0% in the placebo group to 1.2% in both the group receiving 75 mg of pritelivir daily (relative risk, 0.13; 95% CI, 0.02 to 0.70) and the group receiving 400 mg weekly (relative risk, 0.13; 95% CI, 0.03 to 0.52). The rate of adverse events was similar in all groups. CONCLUSIONS Pritelivir reduced the rates of genital HSV shedding and days with lesions in a dose-dependent manner in otherwise healthy men and women with genital herpes. (Funded by AiCuris; ClinicalTrials.gov number, NCT01047540.).
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Affiliation(s)
- Anna Wald
- From the University of Washington and Fred Hutchinson Cancer Research Center, Seattle (A.W., L.C., A.M., C.J., M.-L.H., S. Selke); AiCuris, Wuppertal, Germany (B.T., S. Stoelben, H.-P.S., H.R.-S., A.B.); Westover Heights Clinic, Portland, OR (T.W.); University of Texas, Houston (S.T.); University of Utah, Salt Lake City (J.K.); Indiana University School of Medicine, Indianapolis (K.F.); and Cetero Research, Miami (L.G.)
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Helicase–primase inhibitors for herpes simplex virus: looking to the future of non-nucleoside inhibitors for treating herpes virus infections. Future Med Chem 2014; 6:45-55. [DOI: 10.4155/fmc.13.192] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Helicase–primase inhibitors (HPIs) are the first new family of potent herpes virus (herpes simplex and varicella-zoster virus) inhibitors to go beyond the preliminary stages of investigation since the emergence of the original nucleoside analog inhibitors. To consider the clinical future of HPIs, this review puts the exciting new findings with two HPIs, amenamevir and pritelivir, into the historical context of antiviral development for the prevention and treatment of herpes simplex virus over the last century and, on this basis, the authors speculate on the potential evolution of these and other non-nucleoside inhibitors in the future.
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20
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Weller SK, Kuchta RD. The DNA helicase-primase complex as a target for herpes viral infection. Expert Opin Ther Targets 2013; 17:1119-32. [PMID: 23930666 DOI: 10.1517/14728222.2013.827663] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION The Herpesviridae are responsible for debilitating acute and chronic infections, and some members of this family are associated with human cancers. Conventional anti-herpesviral therapy targets the viral DNA polymerase and has been extremely successful; however, the emergence of drug-resistant virus strains, especially in neonates and immunocompromised patients, underscores the need for continued development of anti-herpes drugs. In this article, we explore an alternative target for antiviral therapy, the HSV helicase/primase complex. AREAS COVERED This review addresses the current state of knowledge of HSV DNA replication and the important roles played by the herpesvirus helicase- primase complex. In the last 10 years several helicase/primase inhibitors (HPIs) have been described, and in this article, we discuss and contrast these new agents with established inhibitors. EXPERT OPINION The outstanding safety profile of existing nucleoside analogues for α-herpesvirus infection make the development of new therapeutic agents a challenge. Currently used nucleoside analogues exhibit few side effects and have low occurrence of clinically relevant resistance. For HCMV, however, existing drugs have significant toxicity issues and the frequency of drug resistance is high, and no antiviral therapies are available for EBV and KSHV. The development of new anti-herpesvirus drugs is thus well worth pursuing especially for immunocompromised patients and those who develop drug-resistant infections. Although the HPIs are promising, limitations to their development into a successful drug strategy remain.
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Affiliation(s)
- Sandra K Weller
- University of Connecticut Health Center, Department of Molecular Microbial and Structural Biology , Farmington CT 06030 , USA +1 860 679 2310 ;
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Shadrick WR, Ndjomou J, Kolli R, Mukherjee S, Hanson AM, Frick DN. Discovering new medicines targeting helicases: challenges and recent progress. ACTA ACUST UNITED AC 2013; 18:761-81. [PMID: 23536547 PMCID: PMC4427233 DOI: 10.1177/1087057113482586] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Helicases are ubiquitous motor proteins that separate and/or rearrange nucleic acid duplexes in reactions fueled by adenosine triphosphate (ATP) hydrolysis. Helicases encoded by bacteria, viruses, and human cells are widely studied targets for new antiviral, antibiotic, and anticancer drugs. This review summarizes the biochemistry of frequently targeted helicases. These proteins include viral enzymes from herpes simplex virus, papillomaviruses, polyomaviruses, coronaviruses, the hepatitis C virus, and various flaviviruses. Bacterial targets examined include DnaB-like and RecBCD-like helicases. The human DEAD-box protein DDX3 is the cellular antiviral target discussed, and cellular anticancer drug targets discussed are the human RecQ-like helicases and eIF4A. We also review assays used for helicase inhibitor discovery and the most promising and common helicase inhibitor chemotypes, such as nucleotide analogues, polyphenyls, metal ion chelators, flavones, polycyclic aromatic polymers, coumarins, and various DNA binding pharmacophores. Also discussed are common complications encountered while searching for potent helicase inhibitors and possible solutions for these problems.
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Affiliation(s)
- William R Shadrick
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
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Abstract
Background Herpesviruses notably establish lifelong infections, with latency and reactivation. Many of the known human herpesviruses infect large proportions of the population worldwide. Treatment or prevention of herpes infections and recurrent disease still pose a challenge in the 21st century. Sources of data Original papers and review articles, meeting abstracts, a book (Clinical Virology; DD Richman, RJ Whitley & FG Hayden eds) and company web sites. Areas of agreement For herpes simplex types 1 and 2 and for varicella zoster, acyclovir (ACV; now increasingly replaced by its prodrug valacyclovir, VACV) and famciclovir (FCV) have greatly reduced the burden of disease and have established a remarkable safety record. Drug-resistance, in the otherwise healthy population, has remained below 0.5% after more that 20 years of antiviral use. In immunocompromised patients, drug resistance is more common and alternative drugs with good safety profiles are desirable. For human cytomegalovirus disease, which occurs in immunocompromised patients, ganciclovir and increasingly its prodrug valganciclovir are the drugs of choice. However, alternative drugs, with better safety, are much needed. Areas of controversy Various questions are highlighted. Should the new 1-day therapies for recurrent herpes labialis and genital herpes replace the current standard multi-day therapies? The marked differences between VACV and FCV (e.g. triphosphate stability, effect on latency) may not yet be fully exploited? Do current antivirals reduce post-herpetic neuralgia (PHN)? For immunocompromised patients with varicella zoster virus (VZV) disease, should the first-line treatment be FCV, not ACV or VACV? Should there be more support to explore new avenues for current antivirals, for example in possibly reducing herpes latency or Alzheimer's disease (AD)? Should primary Epstein-Barr virus (EBV) disease in adolescents be treated with antivirals? How can new compounds be progressed when the perceived market need is small but the medical need is great. FCV was reclassified from prescription-only to pharmacist-controlled for herpes labialis in New Zealand in 2010; should this be repeated more widely? This article reviews new drugs in clinical trials and highlights some of the problems hindering their progress.
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Field HJ, Mickleburgh I. The helicase-primase complex as a target for effective herpesvirus antivirals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 767:145-59. [PMID: 23161010 DOI: 10.1007/978-1-4614-5037-5_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Herpes simplex virus and varicella-zoster virus have been treated for more that half a century using nucleoside analogues. However, there is still an unmet clinical need for improved herpes antivirals. The successful compounds, acyclovir; penciclovir and their orally bioavailable prodrugs valaciclovir and famciclovir, ultimately block virus replication by inhibiting virus-specific DNA-polymerase. The helicase-primase (HP) complex offers a distinctly different target for specific inhibition of virus DNA synthesis. This review describes the synthetic programmes that have already led to two HP-inhibitors (HPI) that have commenced clinical trials in man. One of these (known as AIC 316) continues in clinical development to date. The specificity of HPI is reflected by the ability to select drug-resistant mutants. The role of HP-antiviral resistance will be considered and how the study of cross--resistance among mutants already shows subtle differences between compounds in this respect. The impact of resistance on the drug development in the clinic will also be considered. Finally, herpesvirus latency remains as the most important barrier to a therapeutic cure. Whether or not helicase primase inhibitors alone or in combination with nucleoside analogues can impact on this elusive goal remains to be seen.
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Andrei G, Snoeck R. Advances in the treatment of varicella-zoster virus infections. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2013; 67:107-68. [PMID: 23886000 DOI: 10.1016/b978-0-12-405880-4.00004-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Varicella-zoster virus (VZV) causes two distinct diseases, varicella (chickenpox) and shingles (herpes zoster). Chickenpox occurs subsequent to primary infection, while herpes zoster (usually associated with aging and immunosuppression) appears as a consequence of reactivation of latent virus. The major complication of shingles is postherpetic neuralgia. Vaccination strategies to prevent varicella or shingles and the current status of antivirals against VZV will be discussed in this chapter. Varivax®, a live-attenuated vaccine, is available for pediatric varicella. Zostavax® is used to boost VZV-specific cell-mediated immunity in adults older than 50 years, which results in a decrease in the burden of herpes zoster and pain related to postherpetic neuralgia. Regardless of the availability of a vaccine, new antiviral agents are necessary for treatment of VZV infections. Current drugs approved for therapy of VZV infections include nucleoside analogues that target the viral DNA polymerase and depend on the viral thymidine kinase for their activation. Novel anti-VZV drugs have recently been evaluated in clinical trials, including the bicyclic nucleoside analogue FV-100, the helicase-primase inhibitor ASP2151, and valomaciclovir (prodrug of the acyclic guanosine derivative H2G). Different candidate VZV drugs have been described in recent years. New anti-VZV drugs should be as safe as and more effective than current gold standards for the treatment of VZV, that is, acyclovir and its prodrug valacyclovir.
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Affiliation(s)
- G Andrei
- Department of Microbiology and Immunology, Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
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Birkmann A, Hewlett G, Rübsamen-Schaeff H, Zimmermann H. Helicase–primase inhibitors as the potential next generation of highly active drugs against herpes simplex viruses. Future Virol 2011. [DOI: 10.2217/fvl.11.28] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Since the introduction of the nucleoside analogs decades ago, treatment of herpes simplex virus (HSV) infections has not seen much innovation, except for the development of their respective prodrugs. The inhibitors of the helicase–primase complex of HSV represent a very innovative approach to the treatment of herpesvirus disease, and this article considers the development of some representatives of this class of therapeutics. The molecular and biochemical features of the helicase–primase complex are considered and the development of three inhibitors of helicase–primase, BILS 179 BS, AIC316 and ASP2151, is described. The clinical development of AIC316 is at an advanced stage and displays general safety as well as favorable, long-lasting exposures in healthy volunteers. The first efficacy data from a Phase II trial with more than 150 HSV-2-positive subjects demonstrated dose-dependent antiviral activity.
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Affiliation(s)
- Alexander Birkmann
- AiCuris GmbH & Co. KG, Friedrich-Ebert-Str. 475, 42117 Wuppertal, Germany
| | - Guy Hewlett
- hbsc, Thienhausener Str. 37, 42781 Haan, Germany
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Katsumata K, Chono K, Sudo K, Shimizu Y, Kontani T, Suzuki H. Effect of ASP2151, a herpesvirus helicase-primase inhibitor, in a guinea pig model of genital herpes. Molecules 2011; 16:7210-23. [PMID: 21869749 PMCID: PMC6264763 DOI: 10.3390/molecules16097210] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 08/04/2011] [Accepted: 08/22/2011] [Indexed: 11/29/2022] Open
Abstract
ASP2151 is a herpesvirus helicase-primase inhibitor with antiviral activity against varicella zoster virus and herpes simplex virus types 1 (HSV-1) and 2 (HSV-2). Here, we examined the potency and efficacy of ASP2151 against HSV in vitro and in vivo. We found that ASP2151 was more potent in inhibiting the replication of HSV-1 and HSV-2 in Vero cells in the plaque reduction assay and had greater anti-HSV activity in a guinea pig model of genital herpes than did acyclovir and valacyclovir (VACV), respectively. Oral ASP2151 given from the day of infection reduced peak and overall disease scores in a dose-dependent manner, resulting in complete prevention of symptoms at the dose of 30 mg/kg. The 50% effective dose (ED(50)) values for ASP2151 and VACV were 0.37 and 68 mg/kg, respectively, indicating that ASP2151 was 184-fold more potent than VACV. When ASP2151 was administered after the onset of symptoms, the disease course of genital herpes was suppressed more effectively than by VACV, with a significant reduction in disease score observed one day after starting ASP2151 at 30 mg/kg, whereas the therapeutic effect of VACV was only evident three days after treatment at the highest dose tested (300 mg/kg). This indicated that ASP2151 possesses a faster onset of action and wider therapeutic time window than VACV. Further, virus shedding from the genital mucosa was significantly reduced with ASP2151 at 10 and 30 mg/kg but not with VACV, even at 300 mg/kg. Taken together, our present findings demonstrated the superior potency and efficacy of ASP2151 against HSV.
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Affiliation(s)
- Kiyomitsu Katsumata
- Drug Discovery Research, Astellas Pharma Inc, 21, Miyukigaoka, Tsukuba, Ibaraki, Japan.
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Abstract
INTRODUCTION Varicella-zoster virus (VZV) is the etiological agent of two distinct diseases, varicella (chickenpox) and shingles (herpes zoster). Chickenpox occurs following primary infection, while herpes zoster (usually associated with ageing and immunosuppression) is the consequence of reactivation of the latent virus. Post-herpetic neuralgia is the major complication of shingles. AREAS COVERED This review will discuss vaccination strategies and the current status of antivirals against VZV. A live attenuated vaccine, Varivax, is available for pediatric varicella while Zostavax was developed to boost VZV-specific cell-mediated immunity in adults older than 60 years and, via this mechanism, to decrease the burden of herpes zoster and pain associated with post-herpetic neuralgia. Despite the availability of a vaccine, there is a need for new antiviral agents. Current drugs approved for the treatment of VZV infections include nucleoside analogs that target the viral DNA polymerase and depend on the viral thymidine kinase. Novel anti-VZV drugs have recently been evaluated in clinical trials, including the bicyclic nucleoside analog FV-100, the helicase-primase inhibitor ASP2151 and valomaciclovir (prodrug of the acyclic guanosine derivative H2G). EXPERT OPINION New anti-VZV drugs should be as safe as and more effective than acyclovir and its prodrug valacyclovir (current gold standard for the treatment of VZV).
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Affiliation(s)
- Graciela Andrei
- Rega Institute for Medical Research, Department of Microbiology and Immunology, Laboratory of Virology and Chemotherapy, K.U.Leuven, Belgium.
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Biswas S, Field HJ. Helicase-Primase Inhibitors: A New Approach to Combat Herpes Simplex Virus and Varicella Zoster Virus. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/9783527635955.ch6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Field HJ, Biswas S. Antiviral drug resistance and helicase-primase inhibitors of herpes simplex virus. Drug Resist Updat 2010; 14:45-51. [PMID: 21183396 DOI: 10.1016/j.drup.2010.11.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/22/2010] [Accepted: 11/23/2010] [Indexed: 11/17/2022]
Abstract
A new class of chemical inhibitors has been discovered that interferes with the process of herpesvirus DNA replication. To date, the majority of useful herpesvirus antivirals are nucleoside analogues that block herpesvirus DNA replication by targeting the DNA polymerase. The new helicase-primase inhibitors (HPI) target a different enzyme complex that is also essential for herpesvirus DNA replication. This review will place the HPI in the context of previous work on the nucleoside analogues. Several promising highly potent HPI will be described with a particular focus on the identification of drug-resistance mutations. Several HPI have good pharmacological profiles and are now at the outset of phase II clinical trials. Provided there are no safety issues to stop their progress, this new class of compound will be a major advance in the herpesvirus antiviral field. Furthermore, HPI are likely to have a major impact on the therapy and prevention of herpes simplex virus and varicella zoster in both immunocompetent and immunocompromised patients alone or in combination with current nucleoside analogues. The possibility of acquired drug-resistance to HPI will then become an issue of great practical importance.
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Affiliation(s)
- Hugh J Field
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB30ES, United Kingdom.
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Resistance of herpes simplex viruses to nucleoside analogues: mechanisms, prevalence, and management. Antimicrob Agents Chemother 2010; 55:459-72. [PMID: 21078929 DOI: 10.1128/aac.00615-10] [Citation(s) in RCA: 344] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Herpes simplex viruses (HSV) type 1 and type 2 are responsible for recurrent orolabial and genital infections. The standard therapy for the management of HSV infections includes acyclovir (ACV) and penciclovir (PCV) with their respective prodrugs valacyclovir and famciclovir. These compounds are phosphorylated by the viral thymidine kinase (TK) and then by cellular kinases. The triphosphate forms selectively inhibit the viral DNA polymerase (DNA pol) activity. Drug-resistant HSV isolates are frequently recovered from immunocompromised patients but rarely found in immunocompetent subjects. The gold standard phenotypic method for evaluating the susceptibility of HSV isolates to antiviral drugs is the plaque reduction assay. Plaque autoradiography allows the associated phenotype to be distinguished (TK-wild-type, TK-negative, TK-low-producer, or TK-altered viruses or mixtures of wild-type and mutant viruses). Genotypic characterization of drug-resistant isolates can reveal mutations located in the viral TK and/or in the DNA pol genes. Recombinant HSV mutants can be generated to analyze the contribution of each specific mutation with regard to the drug resistance phenotype. Most ACV-resistant mutants exhibit some reduction in their capacity to establish latency and to reactivate, as well as in their degree of neurovirulence in animal models of HSV infection. For instance, TK-negative HSV mutants establish latency with a lower efficiency than wild-type strains and reactivate poorly. DNA pol HSV mutants exhibit different degrees of attenuation of neurovirulence. The management of ACV- or PCV-resistant HSV infections includes the use of the pyrophosphate analogue foscarnet and the nucleotide analogue cidofovir. There is a need to develop new antiherpetic compounds with different mechanisms of action.
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Dropulic LK, Cohen JI. Update on new antivirals under development for the treatment of double-stranded DNA virus infections. Clin Pharmacol Ther 2010; 88:610-9. [PMID: 20881959 PMCID: PMC3426500 DOI: 10.1038/clpt.2010.178] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
All the currently available antiviral agents used in the treatment of double-stranded (ds) DNA viruses, with the exception of interferon-α, inhibit the same target, the viral DNA polymerase. With increasing reports of the development of resistance of herpes simplex virus (HSV), cytomegalovirus (CMV), and hepatitis B virus (HBV) to some of these drugs, new antiviral agents are needed to treat these infections. Additionally, no drugs have been approved to treat several DNA virus infections, including those caused by adenovirus, smallpox, molluscum contagiosum, and BK virus. We report the status of 10 new antiviral drugs for the treatment of dsDNA viruses. CMX-001 has broad activity against dsDNA viruses; 3 helicase-primase inhibitors, maribavir, and FV-100 have activity against certain herpesviruses; ST-246 inhibits poxviruses; GS-9191 inhibits papillomaviruses; and clevudine and emtricitabine are active against HBV. Most of these drugs have completed at least phase I trials in humans, and many are in additional clinical trials.
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Affiliation(s)
- Lesia K. Dropulic
- Medical Virology Section, Laboratory of Clinical Infectious Diseases, Bldg. 10, Room 11N234, National Institutes of Health, 10 Center Drive, Bethesda, MD 20892
| | - Jeffrey I. Cohen
- Medical Virology Section, Laboratory of Clinical Infectious Diseases, Bldg. 10, Room 11N234, National Institutes of Health, 10 Center Drive, Bethesda, MD 20892
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Sukla S, Biswas S, Birkmann A, Lischka P, Ruebsamen-Schaeff H, Zimmermann H, Field HJ. Effects of therapy using a helicase-primase inhibitor (HPI) in mice infected with deliberate mixtures of wild-type HSV-1 and an HPI-resistant UL5 mutant. Antiviral Res 2010; 87:67-73. [PMID: 20420855 DOI: 10.1016/j.antiviral.2010.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Revised: 04/19/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
Abstract
Point mutations in the HSV-1 UL5 (helicase) gene confer resistance to helicase-primase inhibitors (HPIs), e.g. BAY 57-1293. Such mutations normally occur at a frequency of < or =10(-6)PFU. However, individual HSV-1 laboratory strains and some clinical isolates contained resistance mutations (e.g. UL5: Lys356Asn) at 10(-4)PFU. To address the possibility that pre-existing mutants at high frequency might have an impact on therapy using HPIs, deliberate mixtures were prepared to contain the SC16 UL5: Lys356Asn mutant in SC16 wild-type in the proportion of 1/500 or 1/50PFU. Mice were infected in the neck-skin with 5x10(4)PFU/mouse of wt alone, mutant alone, or the respective mixture. The mutant could not be detected in infectious virus yields from mice inoculated with the 1/500 mixture. However, resistant mutant was recovered from some treated mice inoculated with the 1/50 mixture. All mice inoculated with mixtures remained responsive to BAY 57-1293-therapy with no increase in clinical signs compared to treatment of wt-infected mice.
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Affiliation(s)
- Soumi Sukla
- Department of Veterinary Medicine, University of Cambridge, United Kingdom
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Wilson SS, Fakioglu E, Herold BC. Novel approaches in fighting herpes simplex virus infections. Expert Rev Anti Infect Ther 2009; 7:559-68. [PMID: 19485796 DOI: 10.1586/eri.09.34] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The development of novel strategies to eradicate herpes simplex virus (HSV) is a global public health priority. While acyclovir and related nucleoside analogues provide successful modalities for treatment and suppression, HSV remains highly prevalent worldwide and is a major cofactor fueling the HIV epidemic. HSV is the predominant cause of genital ulcerative disease, and neonatal and sporadic infectious encephalitis. Asymptomatic shedding, which occurs more frequently than previously appreciated, contributes to viral transmission. Acyclovir resistance may be problematic for immunocompromised patients and highlights the need for new safe and effective agents. Ideally, vaccines to prevent infection, drugs to inhibit the establishment of or reactivation from latency, or vaginal microbicides to prevent sexual and perinatal transmission are needed to control the epidemic. This review summarizes current therapeutic options and strategies in development.
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Affiliation(s)
- Sarah S Wilson
- Department of Pediatrics, Albert Einstein College of Medicine, Forchheimer 702, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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Jancel T, Penzak SR. Antiviral Therapy in Patients With Hematologic Malignancies, Transplantation, and Aplastic Anemia. Semin Hematol 2009; 46:230-47. [DOI: 10.1053/j.seminhematol.2009.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kuchta RD, Stengel G. Mechanism and evolution of DNA primases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1804:1180-9. [PMID: 19540940 DOI: 10.1016/j.bbapap.2009.06.011] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Revised: 05/11/2009] [Accepted: 06/02/2009] [Indexed: 01/31/2023]
Abstract
DNA primase synthesizes short RNA primers that replicative polymerases further elongate in order to initiate the synthesis of all new DNA strands. Thus, primase owes its existence to the inability of DNA polymerases to initiate DNA synthesis starting with 2 dNTPs. Here, we discuss the evolutionary relationships between the different families of primases (viral, eubacterial, archael, and eukaryotic) and the catalytic mechanisms of these enzymes. This includes how they choose an initiation site, elongate the growing primer, and then only synthesize primers of defined length via an inherent ability to count. Finally, the low fidelity of primases along with the development of primase inhibitors is described.
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Affiliation(s)
- Robert D Kuchta
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309, USA.
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Biswas S, Field HJ. Herpes simplex virus helicase-primase inhibitors: recent findings from the study of drug resistance mutations. Antivir Chem Chemother 2008; 19:1-6. [PMID: 18610552 DOI: 10.1177/095632020801900101] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
After several decades during which nucleoside analogues (especially acyclovir and penciclovir and their prodrugs) have benefited many patients suffering from herpes simplex virus (HSV) infections, the discovery of the helicase-primase inhibitors (HPIs) represents an interesting new approach. Although antiviral resistance has not been a major problem for nucleoside analogues in immunocompetent patients, the problem of acyclovir resistance in immunocompromised patients is well documented. Several HPIs are extremely potent antiviral compounds and may, therefore, offer an important alternative therapy in these patients. The potential for synergy, not just for the inhibition of virus replication but also to delay the appearance of drug-resistant virus, needs to be thoroughly investigated. The study of resistance to HPIs has been important towards understanding the mechanism of action of these compounds and confirming the target function. However, during the course of our studies on HPI resistance, we have made a number of interesting observations that may be relevant to their clinical use. This article draws attention to the major observations on HPI resistance reported by others and to our own recently published observations that have extended this expanding area of antiviral research.
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Affiliation(s)
- Subhajit Biswas
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
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Abstract
Most of the antiviral agents that have been approved, and are currently used in the treatment of virus infections, are targeted at HIV, HBV, herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV) and HCV or influenza virus. Additional compounds for HIV, HBV, HSV, VZV, CMV, HCV, influenza virus and several other viral infections, for example poxvirus (e.g., variola, vaccinia and monkeypox), respiratory syncytial virus, hemorrhagic fever virus (e.g., Lassa, Rift Valley and Ebola) and enterovirus (e.g., polio, Coxsackie and echo), are still in the experimental stage, that is, under clinical or preclinical development.
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Affiliation(s)
- Erik De Clercq
- Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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Kaufman HE, Varnell ED, Gebhardt BM, Thompson HW, Atwal E, Rübsamen-Waigmann H, Kleymann G. Efficacy of a helicase-primase inhibitor in animal models of ocular herpes simplex virus type 1 infection. J Ocul Pharmacol Ther 2008; 24:34-42. [PMID: 18201137 DOI: 10.1089/jop.2007.0084] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate the effect of BAY 57-1293, a helicase-primase inhibitor, on herpes simplex virus type 1 (HSV-1) reactivation in mice and its efficacy on established disease in rabbits. METHODS BALB/c mice latent for McKrae-strain HSV-1 were reactivated via heat stress, treated with BAY 57-1293, and their corneas were swabbed for virus or the trigeminal ganglia (TG) obtained for quantification of viral DNA. New Zealand white rabbits were infected and treated topically or orally in comparison with trifluridine or valacyclovir. RESULTS Oral BAY 57-1293 suppressed reactivation in HSV-1-infected mice and reduced the viral load in TG up to four orders of magnitude. In the rabbits, the therapeutic efficacies of topical BAY 57-1293 and trifluridine were similar. Once-daily oral BAY 57-1293 was significantly more effective than valacyclovir and as effective as twice a day topical trifluridine. CONCLUSIONS BAY 57-1293 may be more effective than valacyclovir, without the cytotoxicity or potential healing retardation seen with trifluridine. Oral BAY 57-1293 may be a substitute for eye drops as an effective treatment for herpetic keratitis and might be useful in treating stromal keratitis and iritis, as well as preventing recurrences of ocular herpes.
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Affiliation(s)
- Herbert E Kaufman
- Department of Ophthalmology, LSU Eye Center, Louisiana State University Health Sciences Center in New Orleans, New Orleans, LA, USA.
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[Genotyping diagnosis of acyclovir resistant herpes simplex virus]. ACTA ACUST UNITED AC 2007; 55:504-11. [PMID: 17920786 DOI: 10.1016/j.patbio.2007.08.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Accepted: 08/30/2007] [Indexed: 11/23/2022]
Abstract
Herpes simplex virus resistant to acyclovir (ACV) is a major concern among immunocompromised patients. ACV resistance might be due to mutations located in one of the two genes involved in ACV mechanism of action, the thymidine kinase gene (TK, involved in 95% of the cases) and the DNA polymerase gene. TK gene mutations consist, in half of the cases, in nucleotide insertion or deletion, occurring most of the time in G or C homopolymers considered as hot spots. Half of the other cases involves nucleotide substitutions leading to amino acids substitutions. Studies of sensitive strains revealed a high degree of TK polymorphism, many mutations being not implied in ACV resistance. At the present time, resistance detection can be performed by phenotypic tests that require virus culture and results cannot be given to the physician before 7 to 10 days. Genotyping diagnosis performed directly from clinical samples would allow to detect resistance more rapidly, in order to switch quickly to an appropriate treatment by foscarnet or cidofovir.
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