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McMillan RE, Lo MK, Zhang XQ, Beadle JR, Valiaeva N, Garretson AF, Clark AE, Freshman JE, Murphy J, Montgomery JM, Spiropoulou CF, Schooley RT, Hostetler KY, Carlin AF. Enhanced broad spectrum in vitro antiviral efficacy of 3-F-4-MeO-Bn, 3-CN, and 4-CN derivatives of lipid remdesivir nucleoside monophosphate prodrugs. Antiviral Res 2023; 219:105718. [PMID: 37758067 PMCID: PMC10790242 DOI: 10.1016/j.antiviral.2023.105718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/02/2023] [Accepted: 09/06/2023] [Indexed: 10/02/2023]
Abstract
Broad spectrum oral antivirals are urgently needed for the early treatment of many RNA viruses of clinical concern. We previously described the synthesis of 1-O-octadecyl-2-O-benzyl-glycero-3-phospho-RVn (V2043), an orally bioavailable lipid prodrug of remdesivir nucleoside (RVn, GS-441524) with broad spectrum antiviral activity against viruses with pandemic potential. Here we compared the relative activity of V2043 with new RVn lipid prodrugs containing sn-1 alkyl ether or sn-2 glycerol modifications. We found that 3-F-4-MeO-Bn, 3-CN-Bn, and 4-CN-Bn sn-2 glycerol modifications improved antiviral activity compared to V2043 when tested in vitro against clinically important RNA viruses from 5 virus families. These results support the continued development of V2043 and sn-2 glycerol modified RVn lipid prodrugs for the treatment of a broad range of RNA viruses for which there are limited therapies.
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Affiliation(s)
- Rachel E McMillan
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA; Department of Pathology, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Michael K Lo
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, CA, USA
| | - Xing-Quan Zhang
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - James R Beadle
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Nadejda Valiaeva
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Aaron F Garretson
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA; Department of Pathology, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Alex E Clark
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA; Department of Pathology, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Jon E Freshman
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA; Department of Pathology, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Joyce Murphy
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Joel M Montgomery
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, CA, USA
| | - Christina F Spiropoulou
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, CA, USA
| | - Robert T Schooley
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Karl Y Hostetler
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA
| | - Aaron F Carlin
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, CA, USA; Department of Pathology, University of California San Diego, School of Medicine, La Jolla, CA, USA.
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2
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Carlin A, Beadle JR, Clark AE, Gully KL, Moreira FR, Baric RS, Graham RL, Valiaeva N, Leibel SL, Bray W, McMillan RE, Freshman JE, Garretson AF, McVicar RN, Rana T, Zhang XQ, Murphy JA, Schooley RT, Hostetler KY. 1- O-Octadecyl-2- O-benzyl- sn-glyceryl-3- phospho-GS-441524 (V2043). Evaluation of Oral V2043 in a Mouse Model of SARS-CoV-2 Infection and Synthesis and Antiviral Evaluation of Additional Phospholipid Esters with Enhanced Anti-SARS-CoV-2 Activity. J Med Chem 2023; 66:5802-5819. [PMID: 37040439 PMCID: PMC10108740 DOI: 10.1021/acs.jmedchem.3c00046] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Indexed: 04/13/2023]
Abstract
Early antiviral treatments, including intravenous remdesivir (RDV), reduce hospitalization and severe disease caused by COVID-19. An orally bioavailable RDV analog may facilitate earlier treatment of non-hospitalized COVID-19 patients. Here we describe the synthesis and evaluation of alkyl glyceryl ether phosphodiesters of GS-441524 (RVn), lysophospholipid analogs which allow for oral bioavailability and stability in plasma. Oral treatment of SARS-CoV-2-infected BALB/c mice with 1-O-octadecyl-2-O-benzyl-sn-glyceryl-3-phospho-RVn (60 mg/kg orally, once daily for 5 days starting 12h after infection) reduced lung viral load by 1.5 log10 units versus vehicle at day 2 and to below the limit of detection at day 5. Structure/activity evaluation of additional analogs that have hydrophobic ethers at the sn-2 of glycerol revealed improved in vitro antiviral activity by introduction of a 3-fluoro-4-methoxy-substituted benzyl or a 3- or 4-cyano-substituted benzyl. Collectively, our data support the development of RVn phospholipid prodrugs as oral antiviral agents for prevention and treatment of SARS-CoV-2 infections.
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Affiliation(s)
- Aaron
F. Carlin
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
- Department
of Pathology, University of California,
San Diego, La Jolla, California 92093, United States
| | - James R. Beadle
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Alex E. Clark
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Kendra L. Gully
- Department
of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Fernando R. Moreira
- Department
of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Ralph S. Baric
- Department
of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Rachel L. Graham
- Department
of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Nadejda Valiaeva
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Sandra L. Leibel
- Department
of Pediatrics, University of California,
San Diego, La Jolla, California 92093, United States
| | - William Bray
- Department
of Pediatrics, University of California,
San Diego, La Jolla, California 92093, United States
| | - Rachel E. McMillan
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
- Department
of Pathology, University of California,
San Diego, La Jolla, California 92093, United States
| | - Jonathan E. Freshman
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
- Department
of Pathology, University of California,
San Diego, La Jolla, California 92093, United States
| | - Aaron F. Garretson
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
- Department
of Pathology, University of California,
San Diego, La Jolla, California 92093, United States
| | - Rachael N. McVicar
- Sanford
Burnham Prebys Discovery Institute, La Jolla, California 92037, United States
| | - Tariq Rana
- Department
of Pediatrics, University of California,
San Diego, La Jolla, California 92093, United States
| | - Xing-Quan Zhang
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Joyce A. Murphy
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Robert T. Schooley
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
| | - Karl Y. Hostetler
- Department
of Medicine, University of California, San
Diego, La Jolla, California 92093, United States
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3
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Lo MK, Shrivastava-Ranjan P, Chatterjee P, Flint M, Beadle JR, Valiaeva N, Murphy J, Schooley RT, Hostetler KY, Montgomery JM, Spiropoulou CF. Broad-Spectrum In Vitro Antiviral Activity of ODBG-P-RVn: An Orally-Available, Lipid-Modified Monophosphate Prodrug of Remdesivir Parent Nucleoside (GS-441524). Microbiol Spectr 2021; 9:e0153721. [PMID: 34817209 PMCID: PMC8612139 DOI: 10.1128/spectrum.01537-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 10/28/2021] [Indexed: 11/20/2022] Open
Abstract
The necessity for intravenous administration of remdesivir confines its utility for treatment of coronavirus disease 2019 (COVID-19) to hospitalized patients. We evaluated the broad-spectrum antiviral activity of ODBG-P-RVn, an orally available, lipid-modified monophosphate prodrug of the remdesivir parent nucleoside (GS-441524), against viruses that cause diseases of human public health concern, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). ODBG-P-RVn showed 20-fold greater antiviral activity than GS-441524 and had activity nearly equivalent to that of remdesivir in primary-like human small airway epithelial cells. Our results warrant in vivo efficacy evaluation of ODBG-P-RVn. IMPORTANCE While remdesivir remains one of the few drugs approved by the FDA to treat coronavirus disease 2019 (COVID-19), its intravenous route of administration limits its use to hospital settings. Optimizing the stability and absorption of remdesivir may lead to a more accessible and clinically potent therapeutic. Here, we describe an orally available lipid-modified version of remdesivir with activity nearly equivalent to that of remdesivir against emerging viruses that cause significant disease, including Ebola and Nipah viruses. Our work highlights the importance of such modifications to optimize drug delivery to relevant and appropriate human tissues that are most affected by such diseases.
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Affiliation(s)
- Michael K. Lo
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
| | - Punya Shrivastava-Ranjan
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
| | - Payel Chatterjee
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
| | - Mike Flint
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
| | - James R. Beadle
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Nadejda Valiaeva
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Joyce Murphy
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Robert T. Schooley
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Karl Y. Hostetler
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Joel M. Montgomery
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
| | - Christina F. Spiropoulou
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, Georgia, USA
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4
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Schooley RT, Carlin AF, Beadle JR, Valiaeva N, Zhang XQ, Clark AE, McMillan RE, Leibel SL, McVicar RN, Xie J, Garretson AF, Smith VI, Murphy J, Hostetler KY. Rethinking Remdesivir: Synthesis, Antiviral Activity, and Pharmacokinetics of Oral Lipid Prodrugs. Antimicrob Agents Chemother 2021; 65:e0115521. [PMID: 34310217 PMCID: PMC8448143 DOI: 10.1128/aac.01155-21] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/20/2021] [Indexed: 12/19/2022] Open
Abstract
Remdesivir (RDV; GS-5734) is currently the only FDA-approved antiviral drug for the treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The drug is approved for use in adults or children 12 years or older who are hospitalized for the treatment of COVID-19 on the basis of an acceleration of clinical recovery for inpatients with this disease. Unfortunately, the drug must be administered intravenously, restricting its use to those requiring hospitalization for relatively advanced disease. RDV is also unstable in plasma and has a complex activation pathway which may contribute to its highly variable antiviral efficacy in SARS-CoV-2-infected cells. Potent orally bioavailable antiviral drugs for early treatment of SARS-CoV-2 infection are urgently needed, and several, including molnupiravir and PF-07321332, are currently in clinical development. We focused on making simple, orally bioavailable lipid analogs of remdesivir nucleoside (RVn; GS-441524) that are processed to RVn monophosphate, the precursor of the active RVn triphosphate, by a single-step intracellular cleavage. In addition to high oral bioavailability, stability in plasma, and simpler metabolic activation, new oral lipid prodrugs of RVn had submicromolar anti-SARS-CoV-2 activity in a variety of cell types, including Vero E6, Calu-3, Caco-2, human pluripotent stem cell (PSC)-derived lung cells, and Huh7.5 cells. In Syrian hamsters, oral treatment with 1-O-octadecyl-2-O-benzyl-glycero-3-phosphate RVn (ODBG-P-RVn) was well tolerated and achieved therapeutic levels in plasma above the 90% effective concentration (EC90) for SARS-CoV-2. The results suggest further evaluation as an early oral treatment for SARS-CoV-2 infection to minimize severe disease and reduce hospitalizations.
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Affiliation(s)
- Robert T. Schooley
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Aaron F. Carlin
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - James R. Beadle
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Nadejda Valiaeva
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Xing-Quan Zhang
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Alex E. Clark
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Rachel E. McMillan
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Sandra L. Leibel
- Department of Pediatrics, University of California San Diego, School of Medicine, La Jolla, California, USA
- Sanford Consortium for Regenerative Medicine, La Jolla, California, USA
| | - Rachael N. McVicar
- Sanford Consortium for Regenerative Medicine, La Jolla, California, USA
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Jialei Xie
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Aaron F. Garretson
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Victoria I. Smith
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Joyce Murphy
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
| | - Karl Y. Hostetler
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA
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5
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Lo MK, Shrivastava-Ranjan P, Chatterjee P, Flint M, Beadle JR, Valiaeva N, Schooley RT, Hostetler KY, Montgomery JM, Spiropoulou C. Broad-spectrum in vitro antiviral activity of ODBG-P-RVn: an orally-available, lipid-modified monophosphate prodrug of remdesivir parent nucleoside (GS-441524). bioRxiv 2021. [PMID: 34401879 PMCID: PMC8366795 DOI: 10.1101/2021.08.06.455494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The intravenous administration of remdesivir for COVID-19 confines its utility to hospitalized patients. We evaluated the broad-spectrum antiviral activity of ODBG-P-RVn, an orally available, lipid-modified monophosphate prodrug of the remdesivir parent nucleoside (GS-441524) against viruses that cause diseases of human public health concern, including SARS-CoV-2. ODBG-P-RVn showed 20-fold greater antiviral activity than GS-441524 and had near-equivalent activity to remdesivir in primary-like human small airway epithelial cells. Our results warrant investigation of ODBG-P-RVn efficacy in vivo.
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6
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Schooley RT, Carlin AF, Beadle JR, Valiaeva N, Zhang XQ, Clark AE, McMillan RE, Leibel SL, McVicar RN, Xie J, Garretson AF, Smith VI, Murphy J, Hostetler KY. Rethinking Remdesivir: Synthesis, Antiviral Activity and Pharmacokinetics of Oral Lipid Prodrugs. bioRxiv 2021. [PMID: 32869033 PMCID: PMC7457622 DOI: 10.1101/2020.08.26.269159] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Remdesivir (RDV, GS-5734) is currently the only FDA-approved antiviral drug for the treatment of SARS CoV-2 infection. The drug is approved for use in adults or children 12-years or older who are hospitalized for the treatment of COVID-19 on the basis of an acceleration of clinical recovery for inpatients with this disease. Unfortunately, the drug must be administered intravenously, restricting its use to those requiring hospitalization for relatively advanced disease. RDV is also unstable in plasma and has a complex activation pathway which may contribute to its highly variable antiviral efficacy in SARS-CoV-2 infected cells. Potent orally bioavailable antiviral drugs for early treatment of SARS-CoV-2 infection are urgently needed and several including molnupiravir and PF-07321332 are currently in clinical development. We focused on making simple, orally bioavailable lipid analogs of Remdesivir nucleoside (RVn, GS-441524) that are processed to RVn-monophosphate, the precursor of the active RVn-triphosphate, by a single-step intracellular cleavage. In addition to high oral bioavailability, stability in plasma and simpler metabolic activation, new oral lipid prodrugs of RVn had submicromolar anti-SARS-CoV-2 activity in a variety of cell types including Vero E6, Calu-3, Caco-2, human pluripotent stem cell (PSC)-derived lung cells and Huh7.5 cells. In Syrian hamsters oral treatment with ODBG-P-RVn was well tolerated and achieved therapeutic levels in plasma above the EC90 for SARS-CoV-2. The results suggest further evaluation as an early oral treatment for SARS-CoV-2 infection to minimize severe disease and reduce hospitalizations.
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Affiliation(s)
- Robert T Schooley
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Aaron F Carlin
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - James R Beadle
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Nadejda Valiaeva
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Xing-Quan Zhang
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Alex E Clark
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Rachel E McMillan
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Sandra L Leibel
- Department of Pediatrics, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA.,Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA
| | - Rachael N McVicar
- Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA.,Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Jialei Xie
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Aaron F Garretson
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Victoria I Smith
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Joyce Murphy
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
| | - Karl Y Hostetler
- Division of Infectious Diseases and Global Public Health, University of California San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
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7
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Beadle JR, Aldern KA, Zhang XQ, Valiaeva N, Hostetler KY, Schooley RT. Octadecyloxyethyl benzyl tenofovir: A novel tenofovir diester provides sustained intracellular levels of tenofovir diphosphate. Antiviral Res 2019; 171:104614. [PMID: 31550449 DOI: 10.1016/j.antiviral.2019.104614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/19/2019] [Accepted: 09/21/2019] [Indexed: 10/25/2022]
Abstract
Pre-exposure prophylaxis (PrEP) with topically or systemically administered antiretroviral agents can prevent acquisition of human immunodeficiency virus type 1 (HIV-1) infection. However, in clinical trials using tenofovir-containing agents, HIV-1 acquisition is reduced but not eliminated. Incomplete adherence remains the major contributor to failure. Sustained release or long-acting antiretroviral agents may provide better HIV-1 protection by reducing the clinical impact of incomplete adherence. To reduce dosing frequency, we synthesized a novel tenofovir prodrug, octadecyloxyethyl benzyl tenofovir (ODE-Bn-TFV), that is designed to release TFV slowly in tissues, and showed potent anti-HIV activity in vitro (EC50 = 1.7 nM). In cells exposed to 14C labeled TFV, ODE-Bn-TFV or the quickly activated monoester ODE-TFV, rapid cellular uptake for both lipophilic analogs was noted, achieving 50-fold higher levels than unmodified TFV after 48 h. Following exposure to ODE-[8-14C]TFV, the intracellular diphosphate levels were approximately four-fold higher than with ODE-Bn-TFV. However, intracellular TFVpp drug levels fell rapidly yielding a half-life of about two days. TFVpp levels in ODE-Bn-TFV treated cells decreased much more slowly and reached half-maximal levels in about seven days. These results suggest early accumulation of ODE-Bn-TFV followed by sustained intracellular release following cleavage of the ester bonds linking the ODE and benzyl moieties to the active molecular precursor, thereby potentially allowing for less frequent administration than with more rapidly activated forms of tenofovir.
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Affiliation(s)
- James R Beadle
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA
| | - Kathy A Aldern
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA
| | - Xing-Quan Zhang
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA
| | - Nadejda Valiaeva
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA
| | - Karl Y Hostetler
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Robert T Schooley
- Department of Medicine, Division of Infectious Disease and Global Public Health, University of California San Diego, La Jolla, CA, 92093, USA
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8
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Khoury H, He R, Schimmer A, Beadle JR, Hostetler KY, Minden MD. Octadecyloxyethyl Adefovir Exhibits Potent in vitro and in vivo Cytotoxic Activity and Has Synergistic Effects with Ara-C in Acute Myeloid Leukemia. Chemotherapy 2018; 63:225-237. [PMID: 30372692 DOI: 10.1159/000491705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 07/02/2018] [Indexed: 11/19/2022]
Abstract
Acute myeloid leukemia (AML) continues to be a deadly disease, with only 50-70% of patients achieving complete remission and less than 30% of adults having sustained long-term remissions. In order to address these unmet medical needs, we carried out a high-throughput screen of an in-house library of on- and off-patent drugs with the OCI/AML-2 cell line. Through this screen, we discovered adefovir dipi-voxil (adefovir-DP) as being active against human AML. In addition to adefovir-DP, there are second-generation formulations of adefovir, including octadecyloxyethyl adefovir (ODE-adefovir) and hexadecyloxypropyl adefovir (HDP-adefovir), which were designed to overcome the pharmacokinetic problems of the parent compound adefovir. Given the known clinical benefit of nucleoside analogs for the treatment of AML, we undertook studies to evaluate the potential benefit of adefovir-based molecules. In AML cell lines and patient samples, adefovir-DP and ODE-adefovir were highly potent, whereas HDP-adefovir was significantly less active. Interestingly, ODE-adefovir was remarkably less toxic than adefovir-DP towards normal hematopoietic cells. In addition, ODE-adefovir at a dose of 15 mg/kg/day showed potent activity against human AML in a NOD/SCID mouse model, with a reduction of human leukemia in mouse bone marrow of > 40% in all mice tested within 20 days of treatment. Based on its chemical structure, we hypothesized that the cytotoxicity of ODE-adefovir toward AML was through cell cycle arrest and DNA damage. Indeed, ODE-adefovir treatment induced cell cycle arrest in the S phase and increased levels of pH2Ax, indicating the induction of DNA damage. Furthermore, there was an increase in phospho-p53, transactivation of proapoptotic genes and activation of the intrinsic apoptotic pathway. Subsequent investigation unveiled strong synergism between ODE-adefovir and ara-C, making their coadministration of potential clinical benefit. Expression of MRP4, a nucleoside transporter, appeared to influence the response of AML cells to ODE-adefovir, as its inhibition potentiated ODE-adefovir killing. Taken together, our findings indicate that clinical development of ODE-adefovir or related compounds for the treatment of AML is warranted.
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Affiliation(s)
- Haytham Khoury
- Princess Margaret Hospital, Ontario Cancer Institute, Toronto, Ontario, Canada
| | - Ruijuan He
- Princess Margaret Hospital, Ontario Cancer Institute, Toronto, Ontario, Canada
| | - Aaron Schimmer
- Princess Margaret Hospital, Ontario Cancer Institute, Toronto, Ontario, Canada
| | - James R Beadle
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Karl Y Hostetler
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Mark D Minden
- Princess Margaret Hospital, Ontario Cancer Institute, Toronto, Ontario,
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Kumaki Y, Woolcott JD, Roth JP, Mclean TZ, Smee DF, Barnard DL, Valiaeva N, Beadle JR, Hostetler KY. Inhibition of adenovirus serotype 14 infection by octadecyloxyethyl esters of (S)-[(3-hydroxy-2-phosphonomethoxy)propyl]- nucleosides in vitro. Antiviral Res 2018; 158:122-126. [PMID: 30096340 DOI: 10.1016/j.antiviral.2018.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/27/2018] [Accepted: 08/06/2018] [Indexed: 11/25/2022]
Abstract
On September 22, 2008, a physician on Prince of Wales Island, Alaska, notified the Alaska Department of Health and Social Services (ADHSS) of an unusually high number of adult patients with recently diagnosed pneumonia (n = 10), including three persons who required hospitalization and one who died. ADHSS and CDC conducted an investigation to determine the cause and distribution of the outbreak, identify risk factors for hospitalization, and implement control measures. This report summarizes the results of that investigation, which found that the outbreak was caused by adenovirus 14 (Ad14), an emerging adenovirus serotype in the United States that is associated with a higher rate of severe illness compared with other adenoviruses. Among the 46 cases identified in the outbreak from September 1 through October 27, 2008, the most frequently observed characteristics included the following: male (70%), Alaska Native (61%), underlying pulmonary disease (44%), aged > or = 65 years (26%), and current smoker (48%). Patients aged > or = 65 years had a fivefold increased risk for hospitalization. The most commonly reported symptoms were cough (100%), shortness of breath (87%), and fever (74%). Of the 11 hospitalized patients, three required intensive care, and one required mechanical ventilation. One death was reported. Ad14 isolates obtained during the outbreak were identical genetically to those in recent community-acquired outbreaks in the United States which suggests the emergence of a new, and possibly more virulent Ad14 variant. Clinicians should consider Ad14 infection in the differential diagnosis for patients with community-acquired pneumonia, particularly when unexplained clusters of severe respiratory infections are detected.
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Affiliation(s)
- Yohichi Kumaki
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA.
| | - John D Woolcott
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA
| | - Jason P Roth
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA
| | - Tyler Z Mclean
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA
| | - Donald F Smee
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA
| | - Dale L Barnard
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Science, 5600 Old Main Hill, Utah State University, Logan, UT, 84322-5600, USA
| | - Nadejda Valiaeva
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA, 92093, USA
| | - James R Beadle
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Karl Y Hostetler
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA, 92093, USA
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10
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Banerjee NS, Wang HK, Beadle JR, Hostetler KY, Chow LT. Evaluation of ODE-Bn-PMEG, an acyclic nucleoside phosphonate prodrug, as an antiviral against productive HPV infection in 3D organotypic epithelial cultures. Antiviral Res 2018; 150:164-173. [PMID: 29287913 PMCID: PMC5800947 DOI: 10.1016/j.antiviral.2017.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 12/15/2017] [Accepted: 12/19/2017] [Indexed: 12/22/2022]
Affiliation(s)
- N Sanjib Banerjee
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0005, USA.
| | - Hsu-Kun Wang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0005, USA
| | - James R Beadle
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0676, USA
| | - Karl Y Hostetler
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0676, USA
| | - Louise T Chow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0005, USA
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11
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Chen M, Hou J, Tan G, Xie P, Freeman WR, Beadle JR, Hostetler KY, Cheng L. A novel lipid prodrug strategy for sustained delivery of hexadecyloxypropyl 9-[2-(phosphonomethoxy)ethyl]guanine (HDP-PMEG) on unwanted ocular proliferation. Drug Deliv 2017; 24:1703-1712. [PMID: 29115885 PMCID: PMC8241053 DOI: 10.1080/10717544.2017.1399303] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Proliferative vitreoretinopathy (PVR) is a blinding eye disease and there is no effective pharmacological measure to prevent PVR development. The difficulty comes from lack of potent antiproliferative agent and lack of sustained delivery to cover high-risk time window for PVR to develop. Lipid prodrug of PMEG, hexadecyloxypropyl 9-[(2-phosphonomethoxy)ethyl]guanine (HDP-PMEG), was prepared and was evaluated as a pharmacological adjuvant to surgical management of PVR. A dose-escalation study determined that the highest nontoxic dose for intravitreal use in pigmented rabbits was 3 µg per eye. The genotoxicity of HDP-PMEG was harnessed as a perioperative preventative measure against PVR in a rabbit eye model while the sustained intravitreal pharmacological effect was evaluated on a laser-induced fibrovascular model in rat eye. After intravitreal 3 µg, HDP-PMEG particles in the rabbit vitreous was visible for at least 6 weeks. A single 50-min intravitreal infusion of HDP-PMEG demonstrated significant inhibition of PVR formation when compared with the eyes infused with only BSS (BSS vs. HDP-PMEG: estimate = 1.14, OR = 3.1, p = .027). A single intravitreal 104 ng (equivalent to 3 µg for rabbit eye) of HDP-PMEG significantly inhibit laser-induced fibrovascular proliferation in rat eye by 55% (least square mean pixel, BSS = 4763569.5 vs. HDP-PMEG = 2148129.7, p < .0001, generalized estimating equation [GEE]). Retinal fluorescein angiography showed the odds for BSS intervened eyes to have higher-rated FA leaking grades were 38.5 times compared with HDP-PMEG treated eyes (p < .0001, GEE). Our study results indicate that single intravitreal HDP-PMEG may be a promising ocular drug delivery as a perioperative intervention to prevent PVR reoccurrence following primary surgical management.
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Affiliation(s)
- Mei Chen
- a Institute of Ocular Pharmacology , School of Ophthalmology and Optometry, Wenzhou Medical University , Wenzhou , Zhejiang , China.,b Department of Ophthalmology, Dazhou Central Hospital , Dazhou , Sichuan , China
| | - Jiangping Hou
- a Institute of Ocular Pharmacology , School of Ophthalmology and Optometry, Wenzhou Medical University , Wenzhou , Zhejiang , China.,c Department of Ophthalmology, Provincial Hospital Affiliated to Shandong University , Jinan City , Shandong , China
| | - Guilin Tan
- a Institute of Ocular Pharmacology , School of Ophthalmology and Optometry, Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Peng Xie
- a Institute of Ocular Pharmacology , School of Ophthalmology and Optometry, Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - William R Freeman
- d Jacobs Retina Center at Shiley Eye Center, Department of Ophthalmology , University of California San Diego , La Jolla , CA , USA
| | - James R Beadle
- e Department of Medicine , University of California, San Diego and the San Diego Veterans Medical Research Foundation , La Jolla , CA , USA
| | - Karl Y Hostetler
- e Department of Medicine , University of California, San Diego and the San Diego Veterans Medical Research Foundation , La Jolla , CA , USA
| | - Lingyun Cheng
- a Institute of Ocular Pharmacology , School of Ophthalmology and Optometry, Wenzhou Medical University , Wenzhou , Zhejiang , China.,d Jacobs Retina Center at Shiley Eye Center, Department of Ophthalmology , University of California San Diego , La Jolla , CA , USA
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12
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Beadle JR, Valiaeva N, Yang G, Yu JH, Broker TR, Aldern KA, Harden EA, Keith KA, Prichard MN, Hartman T, Buckheit RW, Chow LT, Hostetler KY. Synthesis and Antiviral Evaluation of Octadecyloxyethyl Benzyl 9-[(2-Phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG), a Potent Inhibitor of Transient HPV DNA Amplification. J Med Chem 2016; 59:10470-10478. [PMID: 27933957 DOI: 10.1021/acs.jmedchem.6b00659] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human papillomavirus (HPV) high-risk genotypes such as HPV-16 and HPV-18 cause the majority of anogenital tract carcinomas, including cervical cancer, the second most common malignancy in women worldwide. Currently there are no approved antiviral agents that reduce or eliminate HPV and reverse virus-associated pathology. We synthesized and evaluated several alkoxyalkyl acyclic nucleoside phosphonate diesters and identified octadecyloxyethyl benzyl 9-[(2-phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG) as an active compound which strongly inhibited transient amplification of HPV-11, -16, and -18 origin-containing plasmid DNA in transfected cells at concentrations well below its cytotoxic concentrations. ODE-Bn-PMEG demonstrated increased uptake in human foreskin fibroblast cells and was readily converted in vitro to the active antiviral metabolite, PMEG diphosphate. The P-chiral enantiomers of ODE-Bn-PMEG were obtained and appeared to have equivalent antiviral activities against HPV. ODE-Bn-PMEG is a promising candidate for the local treatment of HPV-16 and HPV-18 and other high-risk types, an important unmet medical need.
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Affiliation(s)
- James R Beadle
- University of California, San Diego , La Jolla, California 92093, United States
| | - Nadejda Valiaeva
- University of California, San Diego , La Jolla, California 92093, United States
| | - Guang Yang
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Jei-Hwa Yu
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Thomas R Broker
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Kathy A Aldern
- University of California, San Diego , La Jolla, California 92093, United States
| | - Emma A Harden
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Kathy A Keith
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Mark N Prichard
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Tracy Hartman
- ImQuest BioSciences , Frederick, Maryland 21704, United States
| | | | - Louise T Chow
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Karl Y Hostetler
- University of California, San Diego , La Jolla, California 92093, United States.,Antiva Biosciences, Inc. , South San Francisco, California 94080, United States
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13
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Ruiz JC, Aldern KA, Beadle JR, Hartline CB, Kern ER, Hostetler KY. Synthesis and Antiviral Evaluation of Alkoxyalkyl Esters of Phosphonopropoxymethyl-Guanine and Phosphonopropoxymethyl-Diaminopurine. ACTA ACUST UNITED AC 2016; 17:89-95. [PMID: 17042330 DOI: 10.1177/095632020601700204] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Phosphonopropoxymethyl-guanine is the methylene phosphonate analogue of acyclovir. Although not highly active against HSV, 4–38 µM of phosphonopropoxymethyl-guanine has been reported to be active against human and murine cytomegalovirus. Recently we found that cido-fovir, when esterified with alkoxyalkyl moieties, showed greatly increased antiviral activity against cytomegalovirus, herpes simplex virus and orthopoxviruses, in vitro. The alkoxyalkyl esters of cidofovir are orally active in murine models of human and murine cytomegalovirus and orthopoxviruses in vivo. To see if the antiviral activity of phosphonopropoxymethyl-guanine, phosphonopropoxymethyl-diaminopurine and phosphonopropoxymethyl-N6-cyclopropyl-diaminopurine could be increased by this approach, we synthesized their hexadecyloxypropyl-and octadecyloxyethyl- esters and evaluated antiviral activity and cytotoxicity in cells infected with HSV-1 and HCMV, in vitro. Marked increases in antiviral activity were noted in the alkoxyalkyl esters of phosphonopropoxymethyl-guanine. Alkoxyalkyl esters of diaminop-urine and N6-cyclopropyl-diaminopurine showed slight increases in activity against HSV-1 and marked increases in activity against HCMV. The results suggest that esterification with alkoxyalkyl moieties may be a generally useful way to increase antiviral activity of nucleoside phosphonates.
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Affiliation(s)
- Jacqueline C Ruiz
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, CA, USA
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14
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Ma F, Nan K, Lee S, Beadle JR, Hou H, Freeman WR, Hostetler KY, Cheng L. Micelle formulation of hexadecyloxypropyl-cidofovir (HDP-CDV) as an intravitreal long-lasting delivery system. Eur J Pharm Biopharm 2014; 89:271-9. [PMID: 25513956 DOI: 10.1016/j.ejpb.2014.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 12/03/2014] [Accepted: 12/08/2014] [Indexed: 12/11/2022]
Abstract
There still is an unmet need for a safe and sustained intravitreal drug delivery system. In this study we are proposing and characterizing a micelle based, clear-media intravitreal drug delivery system using the lipid derivatized nucleoside analog, hexadecyloxypropyl-cidofovir (HDP-CDV, CMX 001). HDP-CDV forms micelles in water and in vitreous supernatant with the critical micelle concentration of 19 μg/mL and 9 μg/mL, respectively at 37 °C. The formed micelles had the average size of 274.7 nm and the Zeta potential of -47.1 mV. Drug release study in the excised rabbit vitreous showed a sustained release profile with a half-life of 2.7 days. The micelle formulation of HDP-CDV demonstrated a good safety profile in two animal species (rabbit and guinea pig) following intravitreal injection. The sustained efficacy was tested in a pretreatment study design and the drug potency was tested in an ongoing herpes simplex virus (HSV-1) retinitis model. The pretreatment studies using single intravitreal injection and later HSV-1 infection revealed at least 9 weeks of vitreous presence and therapeutic level of HDP-CDV, with 71% eyes protection from infection. The treatment study demonstrated that intravitreal administration halted active HSV-1 retinitis in 80% of the infected eyes while cidofovir (CDV) treatment failed to suppress active HSV-1 retinitis. In summary, lipid derivatized nucleoside analogs can be formulated as a micelle intravitreal injection and provides a sustained drug release in vitreous for chronic retinal diseases.
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Affiliation(s)
- Feiyan Ma
- Jacobs Retina Center at Shiley Eye Center, UCSD, La Jolla, CA, USA
| | - Kaihui Nan
- Jacobs Retina Center at Shiley Eye Center, UCSD, La Jolla, CA, USA
| | - SuNa Lee
- Jacobs Retina Center at Shiley Eye Center, UCSD, La Jolla, CA, USA
| | - James R Beadle
- Department of Medicine, San Diego VA Healthcare System and UCSD, La Jolla, CA, USA
| | - Huiyuan Hou
- Jacobs Retina Center at Shiley Eye Center, UCSD, La Jolla, CA, USA
| | | | - Karl Y Hostetler
- Department of Medicine, San Diego VA Healthcare System and UCSD, La Jolla, CA, USA
| | - Lingyun Cheng
- Jacobs Retina Center at Shiley Eye Center, UCSD, La Jolla, CA, USA.
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15
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Isackson PJ, Sutton KA, Hostetler KY, Vladutiu GD. Novel mutations in the gene encoding very long-chain acyl-CoA dehydrogenase identified in patients with partial carnitine palmitoyltransferase II deficiency. Muscle Nerve 2012; 47:224-9. [PMID: 23169530 DOI: 10.1002/mus.23498] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2012] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Twenty-six patients with clinical symptoms of adult onset carnitine palmitoyltransferase II (CPTII) deficiency were examined. All patients had skeletal muscle CPTII enzyme activity levels indicative of heterozygosity for CPT2 mutations, however sequence analysis identified no pathogenic mutations within the CPT2 gene. METHODS Because the reaction product of CPTII is the substrate for very long-chain acyl-CoA dehydrogenase (VLCAD), we examined the ACADVL gene in these patients by sequence analysis. RESULTS Missense mutations within the ACADVL gene were identified in 3 of the patients. CONCLUSIONS The locations of the altered amino acid residues within the crystal structure of VLCAD are on the surface of the molecule and may be involved in interactions with neighboring molecules. These findings support the importance of considering that mutations may be present in the ACADVL gene when a significant partial deficiency is found in CPTII activity, but no mutations in the CPT2 gene can be identified.
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Affiliation(s)
- Paul J Isackson
- Department of Pediatrics, University at Buffalo, Buffalo, New York, USA.
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16
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Kim JS, Beadle JR, Freeman WR, Hostetler KY, Hartmann K, Valiaeva N, Kozak I, Conner L, Trahan J, Aldern KA, Cheng L. A novel cytarabine crystalline lipid prodrug: hexadecyloxypropyl cytarabine 3',5'-cyclic monophosphate for proliferative vitreoretinopathy. Mol Vis 2012; 18:1907-17. [PMID: 22876115 PMCID: PMC3413433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 07/11/2012] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The objectives of this study were to synthesize and characterize two types of cytarabine (Ara-C) lipid produgs and evaluate the prodrugs for sustained intraocular delivery after administration by intravitreal injection. METHODS Hexadecyloxypropyl cytarabine 5'-monophosphate (HDP-P-Ara-C) and hexadecyloxypropyl cytarabine 3',5'-cyclic monophosphate (HDP-cP-Ara-C) were synthesized starting from cytarabine (1-β-D-arabinofuranosylcytosine). Their vitreal clearance profile was simulated using a custom dissolution chamber, in vitro cytotoxicity was evaluated using cell proliferation assays, and in vivo ocular properties in rat and rabbit eyes were assessed using biomicroscopy, indirect ophthalmoscopy, tonometry, electroretinography, and histology. RESULTS HDP-P-Ara-C was cleared from the dissolution chamber (flow rate 2 µL/min) within 7 days. In contrast, HDP-cP-Ara-C, a much more insoluble prodrug, was still detectable 36 days after the dissolution process was started. HDP-P-Ara-C had a 50% cytotoxicity concentration of 52±2.6 μM in human retinal pigment epithelium (ARPE-19) and 32±2.2 µM in a rat Müller cell line, rMC-1. The 50% cytotoxicity concentration values for HDP-cP-Ara-C in ARPE-19 and rMC-1 cells were 50 µM and 25 µM, respectively. HDP-P-Ara-C was not detectable 2 weeks after the highest intravitreal dose (228 µg/rat eye) was injected, and no ocular toxicity was found. With HDP-cP-Ara-C, the drug depot was visible for 26 weeks following a single intravitreal injection (800 µg/rabbit eye). For both compounds, the electroretinogram, intraocular pressure, and other toxicity studies were negative except for the highest dose of HDP-cP-Ara-C (800 µg/eye), which had focal toxicity from the direct touch of the retina and decreased dark adapted a-waves and decreased flicker electroretinogram amplitudes (generalized estimating equations, p=0.039 and 0.01). CONCLUSIONS The cyclic monophosphate prodrug, HDP-cP-Ara-C, was found to have physiochemical properties better suited for sustained delivery of cytarabine to posterior segments of the eye. These properties included limited aqueous solubility, in vitro antiproliferative activity, and good tolerability after injection into rabbit eyes.
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Affiliation(s)
- Jae Suk Kim
- Jacobs Retina Center at Shiley Eye Center, UC San Diego, La Jolla, CA,Department of Ophthalmology, Sanggye Paik Hospital, Inje University, Seoul
| | - James R. Beadle
- Department of Medicine, San Diego VA Healthcare System and UC San Diego, La Jolla, CA
| | | | - Karl Y. Hostetler
- Department of Medicine, San Diego VA Healthcare System and UC San Diego, La Jolla, CA
| | - Kathrin Hartmann
- Jacobs Retina Center at Shiley Eye Center, UC San Diego, La Jolla, CA
| | - Nadejda Valiaeva
- Department of Medicine, San Diego VA Healthcare System and UC San Diego, La Jolla, CA
| | - Igor Kozak
- Jacobs Retina Center at Shiley Eye Center, UC San Diego, La Jolla, CA
| | - Laura Conner
- Jacobs Retina Center at Shiley Eye Center, UC San Diego, La Jolla, CA
| | - Julissa Trahan
- Department of Medicine, San Diego VA Healthcare System and UC San Diego, La Jolla, CA
| | - Kathy A. Aldern
- Department of Medicine, San Diego VA Healthcare System and UC San Diego, La Jolla, CA
| | - Lingyun Cheng
- Jacobs Retina Center at Shiley Eye Center, UC San Diego, La Jolla, CA
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17
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Wang H, Chhablani J, Freeman WR, Beadle JR, Hostetler KY, Hartmann K, Conner L, Aldern KA, Pearson L, Cheng L. Intraocular safety and pharmacokinetics of hexadecyloxypropyl-cidofovir (HDP-CDV) as a long-lasting intravitreal antiviral drug. Invest Ophthalmol Vis Sci 2011; 52:9391-6. [PMID: 22058340 DOI: 10.1167/iovs.11-8293] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate the intraocular safety and pharmacokinetics of hexadecyloxypropyl-cidofovir (HDP-CDV), the hydrolysis product of HDP-cyclic-CDV, a long-lasting intravitreal cidofovir prodrug for cytomegalovirus (CMV) retinitis. METHODS HDP-cyclic-CDV was suspended in phosphate-buffered saline (PBS) at 37°C and formation of HDP-CDV was monitored by high-performance liquid chromatography (HPLC) analysis for 30 weeks. The safety and pharmacokinetics of HDP-CDV intravitreal injections were studied using New Zealand Red rabbits and (14)C labeled HDP-CDV. Ocular tissues from five time points (1, 3, 7, 14, and 35 days) were analyzed by scintillation counting and HPLC to characterize the pharmacokinetics. RESULTS During the hydrolysis study, approximately 35% of the HDP-cyclic-CDV was converted to HDP-CDV. Evaluation of safety found no toxicity after intravitreal injection of HDP-CDV up to 28 μg/eye. Intravitreal pharmacokinetics of HDP-CDV in the retina, choroid, and vitreous followed a two-phase elimination process and elimination half-lives of 8.4 days (retina), 6.9 days (choroid), and 6.2 days (vitreous). In the retina, cidofovir and an unknown metabolite were detected in the first 2 weeks, and the maximum metabolite concentrations were present 48 hours after the maximum HDP-CDV concentration. CONCLUSIONS HDP-cyclic CDV, under simulated physiologic conditions, slowly converts to HDP-CDV, another potent anti-CMV prodrug that may be taken up by retinal cells and metabolized further to the active antiviral metabolite, cidofovir diphosphate. Taken together, these observations help to explain the ability of a single intravitreal dose of HDP-cyclic-CDV to prevent viral retinitis for up to 68 days in a rabbit model.
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Affiliation(s)
- Haiyan Wang
- Shiley Eye Center, University of California San Diego, La Jolla, California 92093-0946, USA
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18
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Ray AS, Hostetler KY. Application of kinase bypass strategies to nucleoside antivirals. Antiviral Res 2011; 92:277-91. [PMID: 21878354 DOI: 10.1016/j.antiviral.2011.08.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 08/17/2011] [Accepted: 08/17/2011] [Indexed: 12/19/2022]
Abstract
Nucleoside and nucleotide analogs have served as the cornerstones of antiviral therapy for many viruses. However, the requirement for intracellular activation and side-effects caused by distribution to off-target sites of toxicity still limit the efficacy of the current generation of drugs. Kinase bypass strategies, where phosphorylated nucleosides are delivered directly into cells, thereby, removing the requirement for enzyme catalyzed phosphorylation steps, have already changed the face of antiviral therapy in the form of the acyclic nucleoside phosphonates, cidofovir, adefovir (given orally as its dipivoxil prodrug) and tenofovir (given orally as its disoproxil prodrug), currently used clinically. These strategies hold further promise to advance the field of antiviral therapy with at least 10 kinase bypass and tissue targeted prodrugs, representing seven distinct prodrug classes, currently in clinical trials. This article reviews the history of kinase bypass strategies applied to nucleoside antivirals and the evolution of different tissue targeted prodrug strategies, highlighting clinically relevant examples.
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Affiliation(s)
- Adrian S Ray
- Gilead Sciences, Inc., Foster City, CA 94404, USA.
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Valiaeva N, Wyles DL, Schooley RT, Hwu JB, Beadle JR, Prichard MN, Hostetler KY. Synthesis and antiviral evaluation of 9-(S)-[3-alkoxy-2-(phosphonomethoxy)propyl]nucleoside alkoxyalkyl esters: inhibitors of hepatitis C virus and HIV-1 replication. Bioorg Med Chem 2011; 19:4616-25. [PMID: 21719300 DOI: 10.1016/j.bmc.2011.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 05/27/2011] [Accepted: 06/02/2011] [Indexed: 12/19/2022]
Abstract
We reported previously that octadecyloxyethyl 9-(S)-[3-hydroxy-2-(phosphonomethoxy)-propyl]adenine (ODE-(S)-HPMPA) was active against genotype 1b and 2a hepatitis C virus (HCV) replicons. This is surprising because acyclic nucleoside phosphonates have been regarded as having antiviral activity only against double stranded DNA viruses, HIV and HBV. We synthesized octadecyloxyethyl 9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]-adenine and found it to be active in genotype 1b and 2a HCV replicons with EC₅₀ values of 1-2 μM and a CC₅₀ of > 150 μM. Analogs with substitutions at the 3'-hydroxyl larger than methyl or ethyl, or with other purine bases were less active but most compounds had significant antiviral activity against HIV-1 in vitro. The most active anti-HIV compound was octadecyloxyethyl 9-(R)-[3-methoxy-2-(phosphonomethoxy)propyl]guanine with an EC₅₀ < 0.01 nanomolar and a selectivity index of > 4.4 million.
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Affiliation(s)
- Nadejda Valiaeva
- Division of Infectious Diseases, University of California, San Diego, USA
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Beadle JR, Hostetler KY. Alkoxyalkyl Ester Prodrugs of Antiviral Nucleoside Phosphates and Phosphonates. Antiviral Drug Strategies 2011. [DOI: 10.1002/9783527635955.ch8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Beadle JR, Cheng L, Hostetler KY, Freeman WR. Intravitreal Alkoxyalkyl Esters of Cyclic Cidofovir for Treatment of Ocular Viral Infections. Antiviral Res 2011. [DOI: 10.1016/j.antiviral.2011.03.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wyles DL, Jones KA, Valiaeva N, Beadle JR, Schooley RT, Hostetler KY. Enhanced Cellular Penetration of ODE-(S)-MPMPA Accounts for Its Prolonged Post-exposure Anti-HCV Activity. Antiviral Res 2011. [DOI: 10.1016/j.antiviral.2011.03.133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cheng L, Beadle JR, Tammewar A, Hostetler KY, Hoh C, Freeman WR. Intraocular pharmacokinetics of a crystalline lipid prodrug, octadecyloxyethyl-cyclic-cidofovir, for cytomegalovirus retinitis. J Ocul Pharmacol Ther 2011; 27:157-62. [PMID: 21351867 DOI: 10.1089/jop.2010.0155] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To evaluate the intraocular pharmacokinetics of octadecyloxyethyl-cyclic-cidofovir (ODE-cCDV) after intravitreal injection into rabbit eyes. METHODS Twenty-seven New Zealand red rabbits (27 eyes) received intravitreal injections of (14)C-labeled ODE-cCDV (100 μg drug suspended in 5% dextrose), and ocular tissues were collected from 3 rabbits at each predetermined time point (1 h, 1 day, 3 days, 1 week, 2 weeks, 3 weeks, 5 weeks, and 9 weeks) after the injection. The eye globes were enucleated, and the vitreous, retina, and choroids were separated and harvested into pre-weighed scintillation vials. Levels of ODE-cCDV were measured by counting in a liquid scintillation counter, and pharmacokinetic (PK) parameters were determined. In addition, 3 eyes of 3 animals were used for autoradiography study at day 1, week 3, and week 6. RESULTS ODE-cCDV in vitreous as a whole followed a 2-phase first-order elimination, whereas ODE-cCDV in retina and choroid manifested a nearly steady state during the first 3 weeks and then followed a first-order elimination with the apparent elimination half-life of 10.1 and 7.2 days. For vitreous, apparent elimination half-life was 25 days. However, the drug mean residence time was much longer in retina (17.6 days) and choroid (19.6 days) than that in the vitreous (11.6 days). The drug exposure to the retina [area under the curve (AUC) = 1120837.1 ng · day/mL] was greater than the exposure to the vitreous (AUC = 958645.8 ng · day/mL) and the choroid (AUC = 415407.47). CONCLUSION A crystalline lipid prodrug, ODE-cCDV, has longer vitreous half-life than that in other ocular tissues due to its solid drug depot formation in vitreous. Over time, dissolved free ODE-cCDV from drug depot feeds and accumulates in the retina.
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Affiliation(s)
- Lingyun Cheng
- Department of Ophthalmology, Jacobs Retina Center at Shiley Eye Center, University of California-San Diego, 9415 Campus Point Drive, La Jolla, CA 92093-0946, USA.
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Julien O, Beadle JR, Magee WC, Chatterjee S, Hostetler KY, Evans DH, Sykes BD. Solution structure of a DNA duplex containing the potent anti-poxvirus agent cidofovir. J Am Chem Soc 2011; 133:2264-74. [PMID: 21280608 DOI: 10.1021/ja109823e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cidofovir (1(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine, CDV) is a potent inhibitor of orthopoxvirus DNA replication. Prior studies have shown that, when CDV is incorporated into a growing primer strand, it can inhibit both the 3'-to-5' exonuclease and the 5'-to-3' chain extension activities of vaccinia virus DNA polymerase. This drug can also be incorporated into DNA, creating a significant impediment to trans-lesion DNA synthesis in a manner resembling DNA damage. CDV and deoxycytidine share a common nucleobase, but CDV lacks the deoxyribose sugar. The acyclic phosphonate bears a hydroxyl moiety that is equivalent to the 3'-hydroxyl of dCMP and permits CDV incorporation into duplex DNA. To study the structural consequences of inserting CDV into DNA, we have used (1)H NMR to solve the solution structures of a dodecamer DNA duplex containing a CDV molecule at position 7 and of a control DNA duplex. The overall structures of both DNA duplexes were found to be very similar. We observed a decrease of intensity (>50%) for the imino protons neighboring the CDV (G6, T8) and the cognate base G18 and a large chemical shift change for G18. This indicates higher proton exchange rates for this region, which were confirmed using NMR-monitored melting experiments. DNA duplex melting experiments monitored by circular dichroism revealed a lower T(m) for the CDV DNA duplex (46 °C) compared to the control (58 °C) in 0.2 M salt. Our results suggest that the CDV drug is well accommodated and stable within the dodecamer DNA duplex, but the stability of the complex is less than that of the control, suggesting increased dynamics around the CDV.
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Affiliation(s)
- Olivier Julien
- Department of Biochemistry, University of Alberta, 4-19 Medical Sciences Building, Edmonton, Alberta T6G 2H7, Canada
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Beadle JR, Chatterjee S, Magee WC, Sykes BD, Evans DH, Hostetler KY. Synthesis and Solution Structure of DNA Duplexes Containing the Potent Anti-poxvirus Agent Cidofovir. Antiviral Res 2010. [DOI: 10.1016/j.antiviral.2010.02.427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Aldern KA, Trahan J, Beadle JR, Su Y, Hostetler KY. Oral Pharmacokinetics of hexadecyloxypropyl 9-(R)-[2-(Phosphono-methoxy)propyl]guanine (HDP-(R)-PMPG) in Mice using LC/MS/MS. Antiviral Res 2010. [DOI: 10.1016/j.antiviral.2010.02.424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Ruiz JC, Aldern KA, Trahan J, Beadle JR, Hostetler KY. Synthesis and Antiviral Evaluation of Alkoxyalkyl Esters of (R)-[2-(Phosphonomethoxy)propyl]-Nucleosides. Antiviral Res 2010. [DOI: 10.1016/j.antiviral.2010.02.467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Valiaeva N, Trahan J, Aldern KA, Beadle JR, Hostetler KY. Antiproliferative effects of octadecyloxyethyl 9-[2-(phosphonomethoxy)ethyl]guanine against Me-180 human cervical cancer cells in vitro and in vivo. Chemotherapy 2010; 56:54-9. [PMID: 20215748 DOI: 10.1159/000292582] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Accepted: 10/16/2009] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS 9-[2-(phosphonomethoxy)ethyl]guanine (PMEG) is one of the most active antiproliferative compounds in a series of acyclic nucleoside phosphonates and is active in intraperitoneal P388 tumors in mice. METHODS We synthesized octadecyloxyethyl (ODE) and hexadecyloxypropyl esters of PMEG and compared their antiproliferative activity with unmodified PMEG in primary human fibroblasts and CaSki, Me-180 and HeLa human cervical cancer cell lines in vitro. RESULTS ODE-PMEG had excellent antiproliferative activity in vitro in this panel of human cervical cancers. We compared the effects of ODE-PMEG and ODE-cidofovir (ODE-CDV) in a solid tumor model using Me-180 human cervical cancer cell lines in athymic nude mice. Intratumoral injection of 25 microg of ODE-PMEG or 100 microg of ODE-CDV daily for 21 days followed by observation for 20-35 days resulted in near-complete disappearance of measurable cervical cancers. CONCLUSION ODE-PMEG may be suitable for local or topical treatment of cervical dysplasia.
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Affiliation(s)
- Nadejda Valiaeva
- Department of Medicine, University of California, San Diego, La Jolla, Calif., and Veterans Medical Research Foundation, San Diego, CA 92093-0676, USA
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Botros SS, William S, Beadle JR, Valiaeva N, Hostetler KY. Antischistosomal activity of hexadecyloxypropyl cyclic 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine and other alkoxyalkyl esters of acyclic nucleoside phosphonates assessed by schistosome worm killing in vitro. Antimicrob Agents Chemother 2009; 53:5284-7. [PMID: 19704122 PMCID: PMC2786359 DOI: 10.1128/aac.00840-09] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 07/17/2009] [Accepted: 08/18/2009] [Indexed: 11/20/2022] Open
Abstract
9-(S)-[3-Hydroxy-2-(phosphonomethoxy)propyl]adenine [(S)-HPMPA] has been reported to have antischistosomal activity. Ether lipid esters of (S)-HPMPA and cidofovir (CDV) have greatly increased activities in antiviral assays and in lethal animal models of poxvirus diseases. To see if ether lipid esters of CDV and (S)-HPMPA enhance antischistosomal activity, we tested their alkoxyalkyl esters using Schistosoma mansoni worm killing in vitro. Hexadecyloxypropyl (HDP)-cyclic-(S)-HPMPA and HDP-cyclic-CDV exhibited significant in vitro antischistosomal activities and may offer promise alone or in combination with praziquantel.
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Affiliation(s)
- Sanaa S. Botros
- Departments of Pharmacology, Parasitology, Theodor Bilharz Research Institute, Warrak el-Hadar, Imbaba, P.O. Box 30, Giza 12411, Egypt, San Diego Veterans Medical Research Foundation and Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, California 92093
| | - Samia William
- Departments of Pharmacology, Parasitology, Theodor Bilharz Research Institute, Warrak el-Hadar, Imbaba, P.O. Box 30, Giza 12411, Egypt, San Diego Veterans Medical Research Foundation and Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, California 92093
| | - James R. Beadle
- Departments of Pharmacology, Parasitology, Theodor Bilharz Research Institute, Warrak el-Hadar, Imbaba, P.O. Box 30, Giza 12411, Egypt, San Diego Veterans Medical Research Foundation and Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, California 92093
| | - Nadejda Valiaeva
- Departments of Pharmacology, Parasitology, Theodor Bilharz Research Institute, Warrak el-Hadar, Imbaba, P.O. Box 30, Giza 12411, Egypt, San Diego Veterans Medical Research Foundation and Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, California 92093
| | - Karl Y. Hostetler
- Departments of Pharmacology, Parasitology, Theodor Bilharz Research Institute, Warrak el-Hadar, Imbaba, P.O. Box 30, Giza 12411, Egypt, San Diego Veterans Medical Research Foundation and Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, California 92093
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Valiaeva N, Prichard MN, Buller RM, Beadle JR, Hartline CB, Keith KA, Schriewer J, Trahan J, Hostetler KY. Antiviral evaluation of octadecyloxyethyl esters of (S)-3-hydroxy-2-(phosphonomethoxy)propyl nucleosides against herpesviruses and orthopoxviruses. Antiviral Res 2009; 84:254-9. [PMID: 19800369 DOI: 10.1016/j.antiviral.2009.09.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 09/22/2009] [Accepted: 09/23/2009] [Indexed: 11/27/2022]
Abstract
Our previous studies showed that esterification of 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine (HPMPA) or 1-(S)-[3-hydroxy-2-(phosphonomethoxy)-propyl]cytosine (HPMPC) with alkoxyalkyl groups such as hexadecyloxypropyl (HDP) or octadecyloxyethyl (ODE) resulted in large increases in antiviral activity and oral bioavailability. The HDP and ODE esters of HPMPA were shown to be active in cells infected with human immunodeficiency virus, type 1 (HIV-1), while HPMPA itself was virtually inactive. To explore this approach in greater detail, we synthesized four new compounds in this series, the ODE esters of 9-(S)-[3-hydroxy-2-(phosphonomethoxy)-propyl]guanine (HPMPG), 1-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]thymine (HPMPT), 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]-2,6-diaminopurine (HPMPDAP) and 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]-2-amino-6-cyclopropylaminopurine (HPMP-cPrDAP) and evaluated their antiviral activity against herpes simplex virus, type 1 (HSV-1), human cytomegalovirus (HCMV), and vaccinia, cowpox and ectromelia. Against HSV-1, subnanomolar EC(50) values were observed with ODE-HPMPA and ODE-HPMPC while ODE-HPMPG had intermediate antiviral activity with an EC(50) of 40 nM. In HFF cells infected with HCMV, the lowest EC(50) values were observed with ODE-HPMPC, 0.9 nM. ODE-HPMPA was highly active with an EC(50) of 3 nM, while ODE-HPMPG and ODE-HPMPDAP were also highly active with EC(50)s of 22 and 77 nM, respectively. Against vaccinia and cowpox viruses, ODE-HPMPG and ODE-HPMPDAP were the most active and selective compounds with EC(50) values of 20-60 nM and selectivity index values of 600-3500. ODE-HPMPG was also active against ectromelia virus with an EC(50) value of 410 nM and a selectivity index value of 166. ODE-HPMPG and ODE-HPMPDAP are proposed for further preclinical evaluation as possible candidates for treatment of HSV, HCMV or orthopoxvirus diseases.
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Affiliation(s)
- Nadejda Valiaeva
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676, USA
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Valiaeva N, Trahan J, Keith KA, Hartline C, Prichard M, Beadle JR, Hostetler KY. Evaluation of Octadecyloxyethyl Esters of 3-Hydroxy-2-(phosphonomethoxy)propyl Nucleosides Against HCMV, HSV and Poxviruses. Antiviral Res 2009. [DOI: 10.1016/j.antiviral.2009.02.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Quenelle DC, Collins DJ, Pettway LR, Hartline CB, Beadle JR, Wan WB, Hostetler KY, Kern ER. Effect of oral treatment with (S)-HPMPA, HDP-(S)-HPMPA or ODE-(S)-HPMPA on replication of murine cytomegalovirus (MCMV) or human cytomegalovirus (HCMV) in animal models. Antiviral Res 2008; 79:133-5. [PMID: 18336926 DOI: 10.1016/j.antiviral.2008.01.155] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 01/18/2008] [Accepted: 01/25/2008] [Indexed: 11/29/2022]
Abstract
We utilized BALB/c mice infected with murine CMV (MCMV) or severe combined immunodeficient (SCID) mice implanted with human fetal tissue and infected with HCMV to determine the efficacy of (S)-9-[3-hydroxy-2-(phophonomethoxy)propyl]adenine ((S)-HPMPA), hexadecyloxypropyl-(S)-HPMPA (HDP-(S)-HPMPA) or octadecyloxyethyl-(S)-HPMPA (ODE-(S)-HPMPA). In MCMV-infected BALB/c mice, oral HDP-(S)-HPMPA at 30 mg/kg significantly reduced mortality when started 24-48 h post inoculation. In the experimental HCMV infection, oral administration of vehicle or 10mg/kg of (S)-HPMPA, HDP-(S)-HPMPA or ODE-(S)-HPMPA was initiated 24h after infection and continued for 28 consecutive days. Cidofovir (CDV), at 20mg/kg given i.p., was used as a positive control. HDP-(S)-HPMPA or ODE-(S)-HPMPA significantly reduced viral replication compared to vehicle-treated mice, while oral (S)-HPMPA was ineffective.
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Tammewar AM, Cheng L, Hostetler KY, Falkenstein I, Beadle JR, Barron EC, Kozak I, Freeman WR. Intraocular Properties of An Alkoxyalkyl Derivative of Cyclic 9-(S)-(3-Hydroxyl-2-Phosphonomehoxypropyl) Adenine, An Intravitreally Injectable Anti-HCMV Drug in Rabbit and Guinea Pig. J Ocul Pharmacol Ther 2007; 23:433-44. [PMID: 17900229 DOI: 10.1089/jop.2007.0018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The aim of this study was to investigate intraocular properties and determine the highest nontoxic dose of hexadecyloxypropyl-cyclic-HPMPA (HDP-cHPMPA), a novel, potent, intravitreally injectable, slow-releasing crystalline drug for long-acting treatment of cytomegalovirus (CMV) retinitis. METHODS Various concentrations of HDP-cHPMPA were first studied in vitro in a human foreskin fibroblast (HFF) cell line infected with human cytomegalovirus (HCMV) to determine the EC50. In vivo, 9 pigmented rabbits and 3 doses (55, 100, and 550 microg/eye) were tested in triplicate in 1 eye of each animal. The eyes were monitored with slit lamp, tonopen, indirect ophthalmoscopy, electroretinography (ERG), and histology. A confirmation toxicity study with the dose equivalent to the highest nontoxic dose in rabbit was performed in 9 guinea pig eyes (a second species) to study the potential adverse effect on intraocular pressure (IOP). RESULTS In vitro testing in HFF cells showed an EC50 against HCMV of 0.02 microM, which is 75- and 60-fold greater than that of ganciclovir and cidofovir, respectively. All eyes injected with 550 microg/eye and 1 eye injected with 100 microg/eye of HDP-cHPMPA showed toxicity clinically (e.g., vitreous cells, disc edema, and retinal inflammation) as well as histologically (e.g., inflammatory cells in iris, vitreous, and retinal layers with disorganization). None of the eyes injected with 55 microg/eye of HDP-cHPMPA showed toxicity clinically (including ERG) and histologically. The equivalent dose (9.2 microg/eye) in the guinea pig eyes did not show toxicity either, including IOP evaluation (P > 0.05 at all time points after injection). CONCLUSIONS Intravitreal injection of the highest nontoxic dose of 55 microg/eye of HDP-cHPMPA in rabbit eyes yields a calculated intravitreal concentration of 65 microM, which is 3250-fold greater than the EC50 against HCMV (0.02 microM). Also, it does not cause hypotony in rabbit and guinea pig eyes and has a vitreous residence time of over 4 months.
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Affiliation(s)
- Ajay M Tammewar
- Jacobs Retina Center at Shiley Eye Center, University of California-San Diego Department of Ophthalmology, La Jolla, San Diego, CA 92037, USA
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Quenelle DC, Collins DJ, Herrod BP, Keith KA, Trahan J, Beadle JR, Hostetler KY, Kern ER. Effect of oral treatment with hexadecyloxypropyl-[(S)-9-(3-hydroxy-2- phosphonylmethoxypropyl)adenine] [(S)-HPMPA] or octadecyloxyethyl-(S)-HPMPA on cowpox or vaccinia virus infections in mice. Antimicrob Agents Chemother 2007; 51:3940-7. [PMID: 17846137 PMCID: PMC2151427 DOI: 10.1128/aac.00184-07] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have previously reported that (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine, or (S)-HPMPA, is active in vitro against cowpox virus (CV) and vaccinia virus (VV) but is not active orally in animals. However, the ether lipid esters of (S)-HPMPA, hexadecyloxypropyl-[(S)-HPMPA] [HDP-(S)-HPMPA] and octadecyloxyethyl-[(S)-HPMPA] [ODE-(S)-HPMPA], had significantly enhanced activity in vitro and are orally bioavailable in mice. In the current study, HDP-(S)-HPMPA and ODE-(S)-HPMPA were prepared in water and administered once daily by oral gavage to mice at doses of 30, 10, and 3 mg/kg of body weight for 5 days beginning 24, 48, or 72 h after inoculation with CV or VV. Oral HDP-(S)-HPMPA and ODE-(S)-HPMPA were both highly effective (P < 0.001) at preventing mortality due to CV at 30 mg/kg, even when treatments were delayed until up to 72 h postinfection. ODE-(S)-HPMPA or HDP-(S)-HPMPA were also highly effective (P < 0.001) at preventing mortality in mice infected with VV at 30 mg/kg when treatments were delayed until to 48 or 72 h postinfection, respectively. Protection against both viruses was associated with a significant reduction of virus replication in the liver, spleen, and kidney but not in the lung. These data indicate that HDP-(S)-HPMPA and ODE-(S)-HPMPA are active when given orally against lethal CV and VV infections in mice, and further evaluation is warranted to provide additional information on the potential of these orally active compounds for treatment of human orthopoxvirus infection.
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Affiliation(s)
- Debra C Quenelle
- Department of Pediatrics, The University of Alabama at Birmingham, School of Medicine, CHB 128, 1600 6th Avenue South, Birmingham, AL 35233, USA.
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Painter GR, Almond MR, Trost LC, Lampert BM, Neyts J, De Clercq E, Korba BE, Aldern KA, Beadle JR, Hostetler KY. Evaluation of hexadecyloxypropyl-9-R-[2-(Phosphonomethoxy)propyl]- adenine, CMX157, as a potential treatment for human immunodeficiency virus type 1 and hepatitis B virus infections. Antimicrob Agents Chemother 2007; 51:3505-9. [PMID: 17646420 PMCID: PMC2043283 DOI: 10.1128/aac.00460-07] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
9-R-[2-(Phosphonomethoxy)propyl]-adenine (tenofovir) is an acyclic nucleoside phosphonate with antiviral activity against human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV). Tenofovir is not orally bioavailable but becomes orally active against HIV-1 infection as the disoproxil ester (tenofovir disoproxil fumarate [Viread]). We have developed an alternative strategy for promoting the oral availability of nucleoside phosphonate analogs which involves esterification with a lipid to form a lysolecithin mimic. This mimic can utilize natural lysolecithin uptake pathways in the gut, resulting in high oral availability. Since the mimic is not subject to cleavage in the plasma by nonspecific esterases, it remains intact in the circulation and facilitates uptake by target cells. Significant drops in apparent antiviral 50% effective concentrations (EC(50)s) of up to 3 logs have been observed in comparison with non-lipid-conjugated parent compounds in target cells. We have applied this technology to tenofovir with the goal of increasing oral availability, decreasing the apparent EC(50), and decreasing the potential for nephrotoxicity by reducing the exposure of the kidney to the free dianionic tenofovir. Here we report that, in vitro, the hexadecyloxypropyl ester of tenofovir, CMX157, is 267-fold more active than tenofovir against HIV-1 and 4.5-fold more active against HBV. CMX157 is orally available and has no apparent toxicity when given orally to rats for 7 days at doses of 10, 30, or 100 mg/kg/day. Consequently, CMX157 represents a second-generation tenofovir analog which may have an improved clinical profile.
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Choo H, Beadle JR, Chong Y, Trahan J, Hostetler KY. Synthesis of the 5-phosphono-pent-2-en-1-yl nucleosides: a new class of antiviral acyclic nucleoside phosphonates. Bioorg Med Chem 2007; 15:1771-9. [PMID: 17166725 PMCID: PMC1810563 DOI: 10.1016/j.bmc.2006.11.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2006] [Accepted: 11/27/2006] [Indexed: 11/24/2022]
Abstract
A new class of acyclic nucleoside phosphonates, the 5-phosphono-pent-2-en-1-yl nucleosides and their hexadecyloxypropyl esters, were synthesized from butyn-1-ol. Only the hexadecyloxypropyl esters showed antiviral activity against herpes simplex virus type 1, in vitro. Hexadecyloxypropyl 1-(5-phosphono-pent-2-en-1-yl)-thymine was the most active and selective compound among the synthesized nucleotides with an EC50 value of 0.90 microM.
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Affiliation(s)
- Hyunah Choo
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676 and the Veterans Medical Research Foundation, San Diego, CA 92161
- Life Sciences Division, Korea Institute of Science and Technology, PO Box 131, Cheongryang, Seoul 130-650, Korea
| | - James R. Beadle
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676 and the Veterans Medical Research Foundation, San Diego, CA 92161
| | - Youhoon Chong
- Division of Biosciences and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, Korea
| | - Julissa Trahan
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676 and the Veterans Medical Research Foundation, San Diego, CA 92161
| | - Karl Y. Hostetler
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676 and the Veterans Medical Research Foundation, San Diego, CA 92161
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Dal Pozzo F, Andrei G, Lebeau I, Beadle JR, Hostetler KY, De Clercq E, Snoeck R. In vitro evaluation of the anti-orf virus activity of alkoxyalkyl esters of CDV, cCDV and (S)-HPMPA. Antiviral Res 2006; 75:52-7. [PMID: 17184854 DOI: 10.1016/j.antiviral.2006.11.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 11/16/2006] [Accepted: 11/27/2006] [Indexed: 10/23/2022]
Abstract
Acyclic nucleoside phosphonates (ANPs) and in particular (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine (HPMPC, cidofovir, CDV, Vistide) and its adenine counterpart (S)-9-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine [(S)-HPMPA] are highly active against orf virus infections. This parapoxvirus commonly causes infection in sheep, goats, but also humans. Alkoxyalkyl esters of CDV have an increased oral bioavailability and are more active against orthopoxviruses than the parent compounds. In the present study, the potency of several alkoxyalkyl esters of CDV, cyclic cidofovir (cCDV) and (S)-HPMPA was evaluated against different orf virus isolates in two cell types, human embryonic lung (HEL) fibroblast and primary lamb keratinocytes. Each prodrug was at least 10-fold more active than its parent compound in both cell types. Of all the compounds tested, the (S)-HPMPA alkoxyalkyl esters showed the highest activity and selectivity against orf virus. Our results support the development of alkoxyalkyl esters of ANPs as antivirals not only for the treatment of complicated human orf lesions, but also in the therapy and prophylaxis of contagious ecthyma in sheep and goats.
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Affiliation(s)
- Fabiana Dal Pozzo
- Rega Institute for Medical Research, K.U.Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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Kornbluth RS, Smee DF, Sidwell RW, Snarsky V, Evans DH, Hostetler KY. Mutations in the E9L polymerase gene of cidofovir-resistant vaccinia virus strain WR are associated with the drug resistance phenotype. Antimicrob Agents Chemother 2006; 50:4038-43. [PMID: 16982794 PMCID: PMC1694007 DOI: 10.1128/aac.00380-06] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Revised: 05/08/2006] [Accepted: 09/07/2006] [Indexed: 11/20/2022] Open
Abstract
Cidofovir (CDV) is an effective drug against viruses of the Orthopoxviridae family and is active in vitro against variola virus, the cause of smallpox. However, CDV-resistant poxviruses can be generated by repeated in vitro passage in the presence of suboptimal concentrations of CDV. To determine if mutations in the E9L polymerase gene could confer resistance to this nucleoside analog, this gene was sequenced from CDV-resistant vaccinia virus and found to encode five amino acid changes, centered on an N-terminal region associated with 3'-->5' exonuclease activity. Transfer of this mutant E9L gene into wild-type vaccinia virus by marker rescue sufficed to confer the resistance phenotype. E9L polymerase mutations occurred sequentially during passage in CDV, and an H296Y/S338F double mutant that conferred an intermediate CDV resistance phenotype was identified. In vitro, the marker-rescued CDV-resistant vaccinia virus containing all five mutations grew nearly as well as wild-type vaccinia virus. However, the virulence of this virus for mice was reduced, as 10- to 30-fold more CDV-resistant virus than wild-type virus was required for lethality following intranasal challenge. Cidofovir and hexadecyloxypropyl-cidofovir gave partial protection to mice infected with the virus when used at 50 and 100 mg/kg of body weight given as single treatments 24 h after virus exposure, whereas 2-amino-7-[(1,3-dihydroxy-2-propoxy)methyl]purine (compound S2242) was completely protective at 25, 50, and 100 mg/kg/day when given daily for 5 days. These findings suggest that drug therapy for poxviruses may be complicated by drug resistance but that treatment of the infection with currently known compounds is possible.
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Affiliation(s)
- Richard S Kornbluth
- Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
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39
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Choo H, Beadle JR, Kern ER, Prichard MN, Keith KA, Hartline CB, Trahan J, Aldern KA, Korba BE, Hostetler KY. Antiviral activities of novel 5-phosphono-pent-2-en-1-yl nucleosides and their alkoxyalkyl phosphonoesters. Antimicrob Agents Chemother 2006; 51:611-5. [PMID: 17130297 PMCID: PMC1797766 DOI: 10.1128/aac.00444-06] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Three acyclic nucleoside phosphonates are currently approved for clinical use against infections caused by cytomegalovirus (Vistide), hepatitis B virus (Hepsera), and human immunodeficiency virus type 1 (Viread). This important antiviral class inhibits viral polymerases after cellular uptake and conversion to their diphosphates, bypassing the first phosphorylation, which is required for conventional nucleoside antivirals. Small chemical alterations in the acyclic side chain lead to marked differences in antiviral activity and the spectrum of activity of acyclic nucleoside phosphonates against various classes of viral agents. We synthesized a new class of acyclic nucleoside phosphonates based on a 5-phosphono-pent-2-en-1-yl base motif in which the oxygen heteroatom usually present in acyclic nucleoside phosphonates has been replaced with a double bond. Since the intrinsic phosphonate moiety leads to low oral bioavailability and impaired cellular penetration, we also prepared the hexadecyloxypropyl esters of the 5-phosphono-pent-2-en-1-yl nucleosides. Our earlier work showed that this markedly increases antiviral activity and oral bioavailability. Although the 5-phosphono-pent-2-en-1-yl nucleosides themselves were not active, the hexadecyloxypropyl esters were active against DNA viruses and hepatitis B virus, in vitro. Notably, the hexadecyloxypropyl ester of 9-(5-phosphono-pent-2-en-1-yl)-adenine was active against hepatitis B virus mutants resistant to lamivudine, emtricitabine, and adefovir.
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Affiliation(s)
- Hyunah Choo
- Department of Medicine (0676), University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
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40
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Hostetler KY, Beadle JR, Trahan J, Aldern KA, Owens G, Schriewer J, Melman L, Buller RM. Oral 1-O-octadecyl-2-O-benzyl-sn-glycero-3-cidofovir targets the lung and is effective against a lethal respiratory challenge with ectromelia virus in mice. Antiviral Res 2006; 73:212-8. [PMID: 17123638 PMCID: PMC1859865 DOI: 10.1016/j.antiviral.2006.10.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 10/11/2006] [Accepted: 10/15/2006] [Indexed: 11/27/2022]
Abstract
Hexadecyloxypropyl-cidofovir (HDP-CDV) has been shown to be orally active against lethal infection with orthopoxviruses including, mousepox, cowpox, vaccinia and rabbitpox. The alkoxyalkyl group provides oral absorption and reduces greatly the amount of drug reaching the kidney, the site of CDV's dose limiting toxicity. However, the amount of HDP-CDV detected in lung, an important site of early poxvirus replication, is low and the reduction of viral titers in surviving animals is reduced moderately compared with the liver where poxvirus titers are virtually undetectable. We synthesized a novel glycerol ester of CDV, 1-O-octadecyl-2-O-benzyl-sn-glycero-3-CDV (ODBG-CDV), and compared its oral pharmacokinetics with that of HDP-CDV. Surprisingly, ODBG-CDV levels in lung are much higher and liver levels are reduced, suggesting that the compound is transported in small intestinal lymph instead the portal vein. ODBG-CDV has excellent in vitro activity in cells infected with ectromelia virus (ECTV). In mice infected with a lethal aerosol or intranasal challenge of ECTV, HDP-CDV and ODBG-CDV are equally effective in preventing death from disease. Other drugs esterified to 1-O-octadecyl-2-O-benzyl-sn-glycerol or 1-O-octadecyl-2-O-benzyl-sn-glycerol-3-phosphate may provide lung targeting for treatment of microbial or neoplastic diseases while reducing first pass removal by the liver during oral absorption.
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Affiliation(s)
- Karl Y Hostetler
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676, United States.
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41
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Ruiz JC, Beadle JR, Aldern KA, Keith KA, Hartline CB, Kern ER, Hostetler KY. Synthesis and antiviral evaluation of alkoxyalkyl-phosphate conjugates of cidofovir and adefovir. Antiviral Res 2006; 75:87-90. [PMID: 17367874 PMCID: PMC1899528 DOI: 10.1016/j.antiviral.2006.09.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 09/13/2006] [Accepted: 09/16/2006] [Indexed: 11/24/2022]
Abstract
Esterification of cidofovir (CDV), an antiviral nucleoside phosphonate, with alkyl or alkoxyalkyl groups increases antiviral activity by enhancing cell uptake and conversion to CDV diphosphate. Hexadecyloxypropyl-CDV (HDP-CDV) has been shown to be 40-100 times more active than CDV in vitro in cells infected with herpes group viruses, variola, cowpox, vaccinia or ectromelia viruses. Since the first phosphorylation of CDV may be rate limiting, we synthesized the hexadecyloxypropyl-phosphate (HDP-P-) and octadecyloxyethyl-phosphate (ODE-P-) conjugates of CDV and phosphonomethoxy-ethyl-adenine (PMEA, adefovir). We tested the CDV analogs in cells infected with human cytomegalovirus, herpes simplex virus, cowpox virus and vaccinia virus; the analogs of PMEA were tested in cells infected with the human immunodeficiency virus, type 1. In general, the alkoxyalkyl-phosphate conjugates of CDV were substantially more active than CDV. HDP-P-CDV and ODE-P-CDV were 4.6-40 times more active against HCMV and 7-30 times more active against cowpox and vaccinia in vitro. Although the compounds of this type were more cytotoxic than the unmodified bases, their selectivity for virally infected cells was generally greater than the parent nucleotides except that HDP-P-PMEA showed little or no selectivity in HIV-1 infected MT-2 cells. Although the new compounds with an interposed phosphate were generally less active than the corresponding alkoxyalkyl esters of CDV and PMEA, the present approach provides a possible alternative method for enhancing the antiviral activity of drugs of this class.
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Affiliation(s)
- Jacqueline C Ruiz
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0676, United States
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42
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Hostetler KY, Aldern KA, Wan WB, Ciesla SL, Beadle JR. Alkoxyalkyl esters of (S)-9-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine are potent inhibitors of the replication of wild-type and drug-resistant human immunodeficiency virus type 1 in vitro. Antimicrob Agents Chemother 2006; 50:2857-9. [PMID: 16870786 PMCID: PMC1538655 DOI: 10.1128/aac.01223-05] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
(S)-9-[3-Hydroxy-2-(phosphonomethoxy)propyl]adenine [(S)-HPMPA], is an effective broad-spectrum antiviral against many DNA viruses but has been reported to be inactive against human immunodeficiency virus (HIV). We synthesized several alkoxyalkyl esters of (S)-HPMPA and now report that hexadecyloxypropyl-(S)-HPMPA [HDP-(S)-HPMPA] and octadecyloxyethyl-(S)-HPMPA [ODE-(S)-HPMPA]had 50% effective concentrations of 0.4 to 7.0 nanomolar and were nearly fully active against HIV variants having reverse transcriptase mutations M184V and K103N and against a zidovudine-resistant variant with mutations D67N, K70R, T215Y, and K219Q. Resistance to HDP-(S)-HPMPA and ODE-(S)-HPMPA was noted for a mutant with mutation K65R. HDP-(S)-HPMPA is also active against herpes simplex virus type 1, human cytomegalovirus, hepatitis B virus, adenoviruses, and orthopoxviruses and is worthy of further evaluation as a possibly therapy for HIV infection.
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Affiliation(s)
- Karl Y Hostetler
- Division of Infectious Disease, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0676, USA.
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43
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Lebeau I, Andrei G, Dal Pozzo F, Beadle JR, Hostetler KY, De Clercq E, van den Oord J, Snoeck R. Activities of alkoxyalkyl esters of cidofovir (CDV), cyclic CDV, and (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine against orthopoxviruses in cell monolayers and in organotypic cultures. Antimicrob Agents Chemother 2006; 50:2525-9. [PMID: 16801436 PMCID: PMC1489770 DOI: 10.1128/aac.01489-05] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The potencies of several alkoxyalkyl esters of acyclic nucleoside phosphonates against vaccinia virus and cowpox virus were evaluated in cell monolayers and three-dimensional epithelial raft cultures. Prodrugs were at least 20-fold more active than their parent compounds. Octadecycloxyethyl-(S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine emerged as the most potent derivative.
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Affiliation(s)
- Ilya Lebeau
- Rega Institute for Medical Research, K.U. Leuven, Minderbroedersstraat 10, Leuven, Belgium.
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Abstract
Polyomavirus BK is a significant pathogen in transplant recipients, but no effective antiviral therapy is available. We show that cidofovir can inhibit BK virus replication in vitro. Esterification of cidofovir with hexadecyloxypropyl, octadecyloxyethyl, and oleyloxyethyl groups results in up to a 3-log lowering of the 50% effective concentration and an increased selectivity index.
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Affiliation(s)
- Parmjeet Randhawa
- Division of Transplantation Pathology, Department of Pathology, University of Pittsburgh Medical Center-Montefiore Hospital, 3459 Fifth Ave., Pittsburgh, PA 15213, USA.
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Valiaeva N, Beadle JR, Aldern KA, Trahan J, Hostetler KY. Synthesis and antiviral evaluation of alkoxyalkyl esters of acyclic purine and pyrimidine nucleoside phosphonates against HIV-1 in vitro. Antiviral Res 2006; 72:10-9. [PMID: 16630664 DOI: 10.1016/j.antiviral.2006.03.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Revised: 03/10/2006] [Accepted: 03/13/2006] [Indexed: 11/23/2022]
Abstract
Alkoxyalkyl esters of cidofovir, an acyclic nucleoside phosphonate, have been shown to have antiviral activities several orders of magnitude greater than unmodified cidofovir against cytomegalovirus, herpes simplex virus, vaccinia, cowpox, ectromelia and adenoviruses in vitro. Hexadecyloxypropyl-cidofovir is orally bioavailable and active in lethal animal models of vaccinia, cowpox, ectromelia and cytomegalovirus. To see if this strategy is also applicable to other acyclic nucleoside phosphonates, we have converted several phosophonomethoxyethyl purines and pyrimidines to their hexadecyloxypropyl, octadecyloxyethyl and oleyloxyethyl esters and compared their activity against HIV-1 with the activity of the respective unmodified acyclic nucleoside phosphonates. The hexadecyloxypropyl esters of phosphonomethoxyethyl-adenine, phosphonomethoxyethyl-2,6-diaminopurine and phosphonomethoxyethyl-N(6)-cyclopropyl-diaminopurine were 3-5 orders of magnitude more active against HIV-1 in vitro than the parent nucleotides. The EC(50) values for these compounds were in the 10-20 pM range with selective indexes of 1,250 to >4,000. The acyclic pyrimidine phosphonates were generally inactive against HIV-1 in vitro. Phosphonomethoxyethyl-cytosine and phosphonomethoxyethyl-5-fluorocytosine were inactive against HIV-1. Surprisingly, hexadecyloxypropyl-phosphonomethoxyethyl-5-fluorocytosine was active against HIV-1 with a submicromolar EC(50) and a selective index of 174. Esterification of acyclic nucleoside phosphonates with alkoxyalkyl moieties may represent a general approach for increasing antiviral activity and selectivity of this class of antivirals.
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Affiliation(s)
- Nadejda Valiaeva
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, USA
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46
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Hostetler KY, Rought S, Aldern KA, Trahan J, Beadle JR, Corbeil J. Enhanced antiproliferative effects of alkoxyalkyl esters of cidofovir in human cervical cancer cells in vitro. Mol Cancer Ther 2006; 5:156-9. [PMID: 16432174 DOI: 10.1158/1535-7163.mct-05-0200] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nearly all cervical cancers are associated with the high-risk subtypes of human papillomavirus (HPV) expressing the E6 and E7 oncoproteins. The E6 and E7 oncoproteins reduce cellular levels of the p53 and the retinoblastoma (pRb) tumor suppressors, respectively, and represent an important component of the malignant phenotype. Several groups have shown that treatment with cidofovir suppresses levels of E6 and E7, restoring cellular p53 and pRb levels, in turn slowing cell replication and increasing the susceptibility of the cancer cells to radiation and apoptosis. Recently, our group synthesized alkoxyalkyl esters of cidofovir, which were found to be >100 times more active than unmodified cidofovir in vitro against various double-stranded DNA viruses, including cytomegalovirus, herpes simplex virus, adenoviruses, cowpox, vaccinia, and variola viruses. We compared the activity of octadecyloxyethyl-cidofovir (ODE-CDV) and oleyloxyethyl-cidofovir (OLE-CDV) with that of unmodified cidofovir against both HPV-negative and HPV-positive cervical cancer cells. We compared the antiproliferation activity in CaSki, HeLa, and Me-180 cells, prototypical HPV-positive cell lines bearing the HPV-16, HPV-18, and HPV-68 high-risk subtypes, with the activity in C33A cells, a cervical cancer cell line lacking HPV, and in nonmalignant primary human foreskin fibroblast cells. OLE-CDV and ODE-CDV were several logs more potent than cidofovir in CaSki, Me-180, HeLa, and C33A cervical cancer cells as determined by 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide inner salt proliferation assay. Cell cycle analysis indicates that the cidofovir analogues interfere with passage of dividing cells through the S phase. ODE-CDV and OLE-CDV were 500 to 17,000 times more active than cidofovir in inhibiting the growth of cervical cancer cells. ODE-CDV and OLE-CDV showed selectivity for cervical cancer cells versus nonmalignant human foreskin fibroblast cells and warrant further investigation as potential therapies for cervical cancer.
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Affiliation(s)
- Karl Y Hostetler
- Department of Medicine, University of California, San Diego, Mail Code 0676, 9500 Gilman Drive, La Jolla, 92093-0676, USA.
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Beadle JR, Wan WB, Ciesla SL, Keith KA, Hartline C, Kern ER, Hostetler KY. Synthesis and Antiviral Evaluation of Alkoxyalkyl Derivatives of 9-(S)-(3-Hydroxy-2-phosphonomethoxypropyl)adenine against Cytomegalovirus and Orthopoxviruses. J Med Chem 2006; 49:2010-5. [PMID: 16539388 DOI: 10.1021/jm050473m] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
9-(S)-(3-Hydroxy-2-phosphonomethoxypropyl)adenine [(S)-HPMPA] was one of the first acyclic nucleoside phosphonates described and has been reported to have good antiviral activity against most double-stranded DNA viruses, including the herpes group viruses and the orthopoxviruses. However, (S)-HPMPA is not orally bioavailable and has not been developed for clinical use. We have prepared orally bioavailable lipid esters of (S)-HPMPA and report their synthesis and antiviral evaluation against cytomegalovirus and orthopoxviruses. These esters were evaluated in vitro in cells infected with human cytomegalovirus (HCMV), murine cytomegalovirus (MCMV), vaccinia (VV), and cowpox viruses (CV). The most active compound, oleyloxyethyl-(S)-HPMPA, was found to have EC50 value of 0.003 microM against HCMV vs 1.4 microM for unmodified HPMPA. In cells infected with VV and CV, octadecyloxyethyl-(S)-HPMPA had EC50 values of 0.01-0.02 microM versus 2.7-4.0 microM for unmodified HPMPA. When compared with the alkoxyalkyl esters of cidofovir, the corresponding alkoxyalkyl esters of (S)-HPMPA were equally active against HCMV and MCMV but were 15-20-fold more active against VV and CV in vitro. The alkoxyalkyl esters of (S)-HPMPA are promising new compounds worthy of further investigation for treatment of infections caused by herpes viruses and orthopoxviruses.
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Affiliation(s)
- James R Beadle
- Department of Medicine, VA San Diego Healthcare System and the University of California, San Diego, La Jolla, California 92093-0676, USA
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48
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Smee DF, Wandersee MK, Bailey KW, Hostetler KY, Holy A, Sidwell RW. Characterization and treatment of cidofovir-resistant vaccinia (WR strain) virus infections in cell culture and in mice. Antivir Chem Chemother 2005; 16:203-11. [PMID: 16004083 DOI: 10.1177/095632020501600306] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The wild-type (WT) vaccinia (WR strain) virus is highly virulent to mice by intranasal inoculation, yet death can be prevented by cidofovir treatment. A cidofovir-resistant (CDV-R) mutant of the virus was developed by 15 Vero cell culture passages in order to determine cross-resistance to other inhibitors, growth characteristics, virulence in infected mice, and suitability of the animal model for studying antiviral therapies. Comparisons were made to the original WT virus and to a WT virus passaged 15 times in culture (WTp15 virus). Cidofovir inhibited WT, WTp15, and CDV-R viruses by 50% at 61, 56 and 790 microM, respectively, in plaque reduction assays, with similar inhibition seen in virus yield studies. Cross-resistance occurred with compounds related to cidofovir, but not with unrelated nucleosides. The resistant virus produced 300-fold fewer infectious particles (PFU) than WT and WTp15 viruses in mouse C1271 cells, yet replicated similarly in Vero (monkey) cells. The CDV-R virus was completely attenuated for virulence at 10(7) PFU per mouse in normal BALB/c mice and in severe combined immunodeficient (SCID) mice. The WTp15 virus was 100-fold less virulent than WT virus in BALB/c mice. Thus, the lack of virulence of the resistant virus in the animal model is explained partly by its reduced ability to replicate in mouse cells and by attenuation occurring as a result of extensive cell culturing (inferred from what occurred with the WTp15 virus). Lung and snout virus titre reduction parameters were used to assess antiviral activity of compounds in BALB/c mice infected intranasally with the CDV-R virus. Cidofovir, HDP-cidofovir and arabinofuranosyladenine treatments reduced lung virus titres <fourfold, and snout virus titres > or = eight-fold. The animal model appears to have limited utility in drug efficacy testing.
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Affiliation(s)
- Donald F Smee
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, UT, USA.
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Williams-Aziz SL, Hartline CB, Harden EA, Daily SL, Prichard MN, Kushner NL, Beadle JR, Wan WB, Hostetler KY, Kern ER. Comparative activities of lipid esters of cidofovir and cyclic cidofovir against replication of herpesviruses in vitro. Antimicrob Agents Chemother 2005; 49:3724-33. [PMID: 16127046 PMCID: PMC1195409 DOI: 10.1128/aac.49.9.3724-3733.2005] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Cidofovir (CDV) is an effective therapy for certain human cytomegalovirus (HCMV) infections in immunocompromised patients that are resistant to other antiviral drugs, but the compound is not active orally. To improve oral bioavailability, a series of lipid analogs of CDV and cyclic CDV (cCDV), including hexadecyloxypropyl-CDV and -cCDV and octadecyloxyethyl-CDV and -cCDV, were synthesized and found to have multiple-log-unit enhanced activity against HCMV in vitro. On the basis of the activity observed with these analogs, additional lipid esters were synthesized and evaluated for their activity against herpes simplex virus (HSV) types 1 and 2, human cytomegalovirus, murine cytomegalovirus, varicella-zoster virus (VZV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), and HHV-8. Using several different in vitro assays, concentrations of drug as low as 0.001 microM reduced herpesvirus replication by 50% (EC50) with the CDV analogs, whereas the cCDV compounds were generally less active. In most of the assays performed, the EC50 values of the lipid esters were at least 100-fold lower than the EC50 values for unmodified CDV or cCDV. The lipid analogs were also active against isolates that were resistant to CDV, ganciclovir, or foscarnet. These results indicate that the lipid ester analogs are considerably more active than CDV itself against HSV, VZV, CMV, EBV, HHV-6, and HHV-8 in vitro, suggesting that they may have potential for the treatment of infections caused by a variety of herpesviruses.
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Affiliation(s)
- Stephanie L Williams-Aziz
- University of Alabama School of Medicine, 1600 6th Ave. South, 128 Children's Harbor Bldg., Birmingham, AL 35233, USA
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Abstract
Cidofovir (CDV) is a broad-spectrum antiviral agent that has been approved for clinical use in the treatment of cytomegalovirus retinitis. It has also been used off label to treat a variety of other viral infections, including those caused by orf and molluscum contagiosum poxviruses. Because it is a dCMP analog, CDV is thought to act by inhibiting viral DNA polymerases. However, the details of the inhibitory mechanism are not well established and nothing is known about the mechanism by which the drug inhibits poxvirus DNA polymerases. To address this concern, we have studied the effect of the active intracellular metabolite of CDV, CDV diphosphate (CDVpp), on reactions catalyzed by vaccinia virus DNA polymerase. Using different primer-template pairs and purified vaccinia virus polymerase, we observed that CDV is incorporated into the growing DNA strand opposite template G's but the enzyme exhibits a lower catalytic efficiency compared with dCTP. CDV-terminated primers are also good substrates for the next deoxynucleoside monophosphate addition step, but these CDV + 1 reaction products are poor substrates for further rounds of synthesis. We also noted that although CDV can be excised from the primer 3' terminus by the 3'-to-5' proofreading exonuclease activity of vaccinia virus polymerase, DNAs bearing CDV as the penultimate 3' residue are completely resistant to exonuclease attack. These results show that vaccinia virus DNA polymerase can use CDVpp as a dCTP analog, albeit one that slows the rate of primer extension. By inhibiting the activity of the proofreading exonuclease, the misincorporation of CDV could also promote error-prone DNA synthesis during poxvirus replication.
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Affiliation(s)
- Wendy C Magee
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, The University of Alberta, Edmonton, AB T6G 2H7, Canada
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