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Poulakou G, Barakat M, Israel RJ, Bacci MR, Álvarez SN, Fonseca FLA, Kainis I, Kalomoiri S, Leontis K, Metallidis S, Panagopoulos P, Papastamopoulos V, Ragognete HG, Ramacciotti E, Rapti V, Sakka V, Syrigos KN, Tsoukalas G, Xynogalas I. Ribavirin aerosol in hospitalized adults with respiratory distress and COVID-19: An open-label trial. Clin Transl Sci 2022; 16:165-174. [PMID: 36326174 PMCID: PMC9841304 DOI: 10.1111/cts.13436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/30/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
Abstract
There is an unmet medical need for effective treatments for hospitalized patients with coronavirus disease 2019 (COVID-19). Ribavirin is a broad-spectrum antiviral with demonstrated in vitro activity against multiple viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This trial evaluated the potential of ribavirin inhalation solution (ribavirin aerosol) to reduce COVID-19 disease severity in adults with confirmed SARS-CoV-2 infection and a diagnosis of respiratory distress. This phase I, multicenter, open-label, nonrandomized trial was conducted from February 2021 through August 2021. Patients received ribavirin aerosol (100 mg/ml for 30 min or 50 mg/ml for 60 min) twice daily for up to 6 days. The primary end point was change from baseline in clinical status severity, rated on a 7-point scale (1 [death]; 7 [not hospitalized; no limitations on activities]), at day 7 (or end-of-treatment/early termination) and day 30 (follow-up). Fifty-one patients were treated with ribavirin aerosol (mean age, 51.5 years; 78.4% men); mean number of doses was 9.7 (range, 1-12). Improvement of ≥1 level in clinical status severity was observed in 31.4% (16/51) and 78.4% (40/51) of patients at end-of-treatment and day 30, respectively. Of 21 patients who required a ventilator, 16 (76.2%) were able to discontinue ventilator use. Five patients (9.8%) died between end-of-treatment and day 30. Three patients (5.9%) discontinued study treatment due to adverse events. No deaths were considered related to study treatment. These data provide preliminary evidence that ribavirin aerosol may be an efficacious treatment for respiratory distress in adults with COVID-19.
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Affiliation(s)
- Garyfallia Poulakou
- Third Department of Internal Medicine, “Sotiria” General Hospital of Chest DiseasesNational and Kapodistrian University of Athens School of MedicineAthensGreece
| | | | | | - Marcelo R. Bacci
- Clinical Analysis Division, Praxis Pesquisa MedicaCentro Universitário Faculdade de Medicina do ABCSanto AndreSão PauloBrazil
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2
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Soto JA, Galvez NMS, Rivera DB, Díaz FE, Riedel CA, Bueno SM, Kalergis AM. From animal studies into clinical trials: the relevance of animal models to develop vaccines and therapies to reduce disease severity and prevent hRSV infection. Expert Opin Drug Discov 2022; 17:1237-1259. [PMID: 36093605 DOI: 10.1080/17460441.2022.2123468] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
INTRODUCTION Human respiratory syncytial virus (hRSV) is an important cause of lower respiratory tract infections in the pediatric and the geriatric population worldwide. There is a substantial economic burden resulting from hRSV disease during winter. Although no vaccines have been approved for human use, prophylactic therapies are available for high-risk populations. Choosing the proper animal models to evaluate different vaccine prototypes or pharmacological treatments is essential for developing efficient therapies against hRSV. AREAS COVERED This article describes the relevance of using different animal models to evaluate the effect of antiviral drugs, pharmacological molecules, vaccine prototypes, and antibodies in the protection against hRSV. The animal models covered are rodents, mustelids, bovines, and nonhuman primates. Animals included were chosen based on the available literature and their role in the development of the drugs discussed in this manuscript. EXPERT OPINION Choosing the correct animal model is critical for exploring and testing treatments that could decrease the impact of hRSV in high-risk populations. Mice will continue to be the most used preclinical model to evaluate this. However, researchers must also explore the use of other models such as nonhuman primates, as they are more similar to humans, prior to escalating into clinical trials.
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Affiliation(s)
- J A Soto
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - N M S Galvez
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - D B Rivera
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - F E Díaz
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - C A Riedel
- Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - S M Bueno
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - A M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Messina E, Danise A, Ferrari G, Andolina A, Chiurlo M, Razanakolona M, Barakat M, Israel RJ, Castagna A. Ribavirin Aerosol in the Treatment of SARS-CoV-2: A Case Series. Infect Dis Ther 2021; 10:2791-2804. [PMID: 34302258 PMCID: PMC8302211 DOI: 10.1007/s40121-021-00493-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/28/2021] [Indexed: 01/29/2023] Open
Abstract
Ribavirin is an inosine monophosphate dehydrogenase inhibitor with demonstrated activity against coronaviruses, including SARS-CoV-2. Five hospitalized patients with COVID-19 (confirmed by positive tests for SARS-CoV-2) received treatment with ribavirin for inhalation solution (ribavirin aerosol) as part of a compassionate use program. Patients included four men and one woman, with an age range of 29–72 years. Patients were managed according to international and Italian treatment guidelines for COVID-19. In addition, therapy with ribavirin aerosol 100 mg/mL was administered for 30 min twice daily for 6 days (i.e., 12 doses) in all patients. In order to address concerns about a possible increase in viral dispersal with the use of a nebulizer, healthcare providers remained outside the patient room during ribavirin aerosol administration. Pretreatment chest computed tomography (CT) scans showed pseudonodular areas of parenchymal thickening in the upper right lobe with associated ground glass opacities, multiple areas of parenchymal consolidation in both lower lobes with associated ground glass opacities, bilateral parenchymal thickening and multiple associated ground glass areas, or focal ground glass areas in the upper lobes bilaterally, which were almost completely resolved (three patients) or moderately cleared (one patient) on imaging at the end of ribavirin treatment. For a fifth patient, CT scans showed a stable pulmonary picture at the end of ribavirin treatment. No adverse reactions to ribavirin treatment were observed in any of the five patients. All patients recovered fully, and nasopharyngeal swabs obtained after hospital discharge tested negative for SARS-CoV-2. Ribavirin aerosol appears to be efficacious in the treatment of patients with COVID-19. A controlled trial of ribavirin aerosol is ongoing and will provide additional data across a broader patient population.
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Affiliation(s)
- Emanuela Messina
- Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Anna Danise
- Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Giulio Ferrari
- Cornea and Ocular Surface Unit, San Raffaele Scientific Institute, Milan, Italy
| | - Andrea Andolina
- Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Matteo Chiurlo
- Infectious Diseases Unit, Vita-Salute San Raffaele University, Milan, Italy
| | - Marie Razanakolona
- Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | | | | | - Antonella Castagna
- Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy. .,Infectious Diseases Unit, Vita-Salute San Raffaele University, Milan, Italy.
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Kosugi Y, Saito Y, Mori S, Watanabe J, Baba M, Shigeta S. Antiviral Activities of Mizoribine and other Inosine Monophosphate Dehydrogenase Inhibitors against Several Ortho- and Paramyxoviruses. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/095632029400500603] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mizoribine (4-carbamoyl-1-β-D-ribofuranosylimidazo-lelium-5-olate), EICAR (5-ethynyl-1-β-D-ribofuranosylimi-dazole-4-carboxamide), mycophenolic acid and ribavirin are antiviral agents targeted for inosine monophosphate (IMP) dehydrogenase. These compounds have been examined for their activities against orthomyxoviruses [influenza viruses (FluV)] and paramyxoviruses [parainfluenza viruses (PFIuV), mumps virus, measles virus (MLSV) and respiratory syncytial virus (RSV)] in vitro. Mizoribine was 1- to 9-fold more active than ribavirin against RSV, PFIuV and MLSV. EICAR and mycophenolic acid showed higher potency than mizoribine and ribavirin against all myxoviruses examined. None of the four compounds examined proved cytotoxic to stationary host cells (HeLa, Vero and MDCK) at a concentration of 200 μg ml−1 or more. On the other hand, EICAR and mycophenolic acid were toxic to rapidly growing cells at concentrations of 2.2-9 and 0.1-1.1 μg ml−1, respectively. Mizoribine and ribavirin showed cytotoxicity to the growing cells at higher concentrations (12-51 μg ml−1). The antiviral activities of mizoribine against FluV and RSV were reversed by 25-100 μm of each of guanosine and guanosine monophosphate (GMP). The antiviral activity of ribavirin against FluV was reversed by 25 μg of each of guanosine and GMP, while its activity against RSV was reversed by ≥ 100 μm of each of these compounds. Neither xanthosine nor xanthosine monophosphate (XMP) reversed the antiviral effects of mizoribine and ribavirin at concentrations of 300 μM. Concentrations 9 times higher than the median effective doses (EC50) of mizoribine and ribavirin inhibited the growth of RSV in HeLa cells as determined in an assay of infectious virus yield. Mizoribin should be further pursued as a candidate drug for the treatment of ortho- and paramyxovirus infections.
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Affiliation(s)
- Y. Kosugi
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
| | - Y. Saito
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
- Life Science Institutes, Asahi Chemical Industry Co., LTD, Ohito, Shizuoka 410-23, Japan
| | - S. Mori
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
| | - J. Watanabe
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
| | - M. Baba
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
| | - S. Shigeta
- Department of Microbiology, Fukushima Medical College, Fukushima 960-12, Japan
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Velkov T, Abdul Rahim N, Zhou Q(T, Chan HK, Li J. Inhaled anti-infective chemotherapy for respiratory tract infections: successes, challenges and the road ahead. Adv Drug Deliv Rev 2015; 85:65-82. [PMID: 25446140 PMCID: PMC4429008 DOI: 10.1016/j.addr.2014.11.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 11/04/2014] [Accepted: 11/05/2014] [Indexed: 12/31/2022]
Abstract
One of the most common causes of illnesses in humans is from respiratory tract infections caused by bacterial, viral or fungal pathogens. Inhaled anti-infective drugs are crucial for the prophylaxis and treatment of respiratory tract infections. The benefit of anti-infective drug delivery via inhalation is that it affords delivery of sufficient therapeutic dosages directly to the primary site of infection, while minimizing the risks of systemic toxicity or avoiding potential suboptimal pharmacokinetics/pharmacodynamics associated with systemic drug exposure. This review provides an up-to-date treatise of approved and novel developmental inhaled anti-infective agents, with particular attention to effective strategies for their use, pulmonary pharmacokinetic properties and safety.
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Cleaver JO, You D, Michaud DR, Guzmán Pruneda FA, Leiva Juarez MM, Zhang J, Weill PM, Adachi R, Gong L, Moghaddam S, Poynter ME, Tuvim MJ, Evans SE. Lung epithelial cells are essential effectors of inducible resistance to pneumonia. Mucosal Immunol 2014; 7:78-88. [PMID: 23632328 PMCID: PMC3735803 DOI: 10.1038/mi.2013.26] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 03/22/2013] [Indexed: 02/04/2023]
Abstract
Infectious pneumonias are the leading cause of death worldwide, particularly among immunocompromised patients. Therapeutic stimulation of the lungs' intrinsic defenses with a unique combination of inhaled Toll-like receptor (TLR) agonists broadly protects mice against otherwise lethal pneumonias. As the survival benefit persists despite cytotoxic chemotherapy-related neutropenia, the cells required for protection were investigated. The inducibility of resistance was tested in mice with deficiencies of leukocyte lineages due to genetic deletions and in wild-type mice with leukocyte populations significantly reduced by antibodies or toxins. Surprisingly, these serial reductions in leukocyte lineages did not appreciably impair inducible resistance, but targeted disruption of TLR signaling in the lung epithelium resulted in complete abrogation of the protective effect. Isolated lung epithelial cells were also induced to kill pathogens in the absence of leukocytes. Proteomic and gene expression analyses of isolated epithelial cells and whole lungs revealed highly congruent antimicrobial responses. Taken together, these data indicate that lung epithelial cells are necessary and sufficient effectors of inducible resistance. These findings challenge conventional paradigms about the role of epithelia in antimicrobial defense and offer a novel potential intervention to protect patients with impaired leukocyte-mediated immunity from fatal pneumonias.
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Affiliation(s)
- Jeffrey O. Cleaver
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Dahui You
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Danielle R. Michaud
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Francisco A. Guzmán Pruneda
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America,Tecnológico de Monterrey School of Medicine, Monterrey, Nuevo León, Mexico
| | | | - Jiexin Zhang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Patrick M. Weill
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Roberto Adachi
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America,Center for Infectious and Inflammatory Disease, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Lei Gong
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Seyed Moghaddam
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America,Center for Infectious and Inflammatory Disease, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Matthew E. Poynter
- Division of Pulmonary Disease and Critical Care, University of Vermont College of Medicine, Burlington, Vermont, United States of America
| | - Michael J. Tuvim
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America,Center for Infectious and Inflammatory Disease, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Scott E. Evans
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America,Center for Infectious and Inflammatory Disease, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America,University of Texas Graduate School of Biomedical Science, Houston, Texas, United States of America
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7
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Tuvim MJ, Gilbert BE, Dickey BF, Evans SE. Synergistic TLR2/6 and TLR9 activation protects mice against lethal influenza pneumonia. PLoS One 2012; 7:e30596. [PMID: 22299046 PMCID: PMC3267724 DOI: 10.1371/journal.pone.0030596] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 12/23/2011] [Indexed: 12/22/2022] Open
Abstract
Lower respiratory tract infections caused by influenza A continue to exact unacceptable worldwide mortality, and recent epidemics have emphasized the importance of preventative and containment strategies. We have previously reported that induction of the lungs' intrinsic defenses by aerosolized treatments can protect mice against otherwise lethal challenges with influenza A virus. More recently, we identified a combination of Toll like receptor (TLR) agonists that can be aerosolized to protect mice against bacterial pneumonia. Here, we tested whether this combination of synthetic TLR agonists could enhance the survival of mice infected with influenza A/HK/8/68 (H3N2) or A/California/04/2009 (H1N1) influenza A viruses. We report that the TLR treatment enhanced survival whether given before or after the infectious challenge, and that protection tended to correlate with reductions in viral titer 4 d after infection. Surprisingly, protection was not associated with induction of interferon gene expression. Together, these studies suggest that synergistic TLR interactions can protect against influenza virus infections by mechanisms that may provide the basis for novel therapeutics.
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Affiliation(s)
- Michael J. Tuvim
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Brian E. Gilbert
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Burton F. Dickey
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Scott E. Evans
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
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8
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Treanor JJ. Viral infections of the respiratory tract: prevention and treatment. Int J Antimicrob Agents 2010; 4:1-22. [PMID: 18611586 DOI: 10.1016/0924-8579(94)90060-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/1993] [Indexed: 10/27/2022]
Abstract
The rapid discovery of specific viral agents as the cause of many acute respiratory diseases was accompanied by considerable optimism that vaccines or other control measures could be developed quickly. Subsequent experience has demonstrated that effective control of these important public health problems has been an elusive goal. However, recent exciting developments in our understanding of the molecular biology and immunology of these viruses may provide the basis for more effective strategies in the future.
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Affiliation(s)
- J J Treanor
- Infectious Diseases Unit, Department of Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA
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9
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Augmented lung inflammation protects against influenza A pneumonia. PLoS One 2009; 4:e4176. [PMID: 19137067 PMCID: PMC2613561 DOI: 10.1371/journal.pone.0004176] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 12/04/2008] [Indexed: 11/19/2022] Open
Abstract
Background Influenza pneumonia causes high mortality every year, and pandemic episodes kill millions of people. Influenza-related mortality has been variously ascribed to an ineffective host response that fails to limit viral replication, an excessive host inflammatory response that results in lung injury and impairment of gas exchange, or to bacterial superinfection. We sought to determine whether lung inflammation promoted or impaired host survival in influenza pneumonia. Methods and Findings To distinguish among these possible causes of influenza-related death, we induced robust lung inflammation by exposing mice to an aerosolized bacterial lysate prior to challenge with live virus. The treatment induced expression of the inflammatory cytokines IL-6 and TNF in bronchoalveolar lavage fluid 8- and 40-fold greater, respectively, than that caused by lethal influenza infection. Yet, this augmented inflammation was associated with striking resistance to host mortality (0% vs 90% survival, p = 0.0001) and reduced viral titers (p = 0.004). Bacterial superinfection of virus infected lungs was not observed. When mice were repeatedly exposed to the bacterial lysate, as would be clinically desirable during an influenza epidemic, there was no tachyphylaxis of the induced viral resistance. When the bacterial lysate was administered after the viral challenge, there was still some mortality benefit, and when ribavirin was added to the aerosolized bacterial lysate, host survival was synergistically improved (0% vs 93.3% survival, p<0.0001). Conclusions Together, these data indicate that innate immune resistance to influenza can be effectively stimulated, and suggest that ineffective rather than excessive inflammation is the major cause of mortality in influenza pneumonia.
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10
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Gilbert BE, McLeay MT. MegaRibavirin aerosol for the treatment of influenza A virus infections in mice. Antiviral Res 2008; 78:223-9. [PMID: 18281104 DOI: 10.1016/j.antiviral.2008.01.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 01/04/2008] [Accepted: 01/08/2008] [Indexed: 10/22/2022]
Abstract
While newer neuraminidase inhibitors have been used recently to treat influenza A and B virus infections, emergence of drug resistance poses potential problems. Previous ribavirin aerosol treatments of influenza were effective and drug resistance was not observed. To make ribavirin aerosol treatment a quicker process and limited to once or twice daily treatments, a MegaRibavirin formulation (100 mg of ribavirin/mL) was developed that when used with the Aerotech II nebulizer was effective in preventing death in a lethal influenza A virus mouse model. Aerosol generated using the Aerotech II nebulizer flowing at 10 L of air/min produced aerosol droplets that contained 2.3 mg of ribavirin/L with a mass median aerodynamic diameter of 1.8 microm. Using this system for treatment, a single daily 30-min exposure on days 1-4 produced a survival rate of greater than 90%. Delaying the start of aerosol treatment for 48 or 72 h and treating once daily for 30 min for two days (days 2-3 and 3-4, respectively) still significantly increased the number of survivors and mean time to death. For the treatment of influenza in general and for pandemic avian influenza, the MegaRibavirin-Aerotech II method of aerosol treatment allows for short treatment periods, minimizes environmental issues and costs less.
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Affiliation(s)
- Brian E Gilbert
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM-280, Houston, TX 77030, United States.
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11
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Abstract
Respiratory syncytial virus (RSV) continues as an emerging infectious disease not only among infants and children, but also for the immune-suppressed, hospitalised and the elderly. To date, ribavirin (Virazole, ICN Pharmaceuticals, Inc.) remains the only therapeutic agent approved for the treatment of RSV. However, its clinical benefits are small and occur only in a fraction of RSV-infected patients. The prophylactic administration of palivizumab (Synagis, MedImmune, Inc.) is problematic and costly and, therefore, only recommended for use in high-risk infants. Clearly, the need for an effective and safe drug remains high. This review discusses several different antisense approaches and compares them with traditional strategies, such as RSV-targeting antibodies and antivirals, as well as developments in vaccine research.
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Affiliation(s)
- Hagen Cramer
- Ridgeway Biosystems, Inc., 9500 Euclid Avenue, ND-50, Cleveland, OH 44195, USA.
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Cramer H, Okicki JR, Kuang M, Xu Z. Targeted therapy of respiratory syncytial virus by 2-5A antisense. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 24:497-501. [PMID: 16247978 DOI: 10.1081/ncn-200061780] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Respiratory syncytial virus is a leading cause of respiratory disease in infants, young children, immunocompromized patients, and the elderly. Previous work has shown that RNase L, an antiviral enzyme of the interferon system, can be recruited to cleave RSVgenomic RNA by attaching tetrameric 2' 5'-linked oligoadenylates (2 5A) to an antisense oligonucleotide complementary to repetitive intergenic sequences within the RSV genome (2 5A antisense). RBI034, a 2'-O-methyl RNA-modified analogue of the 2 5A anti-RSV compound, was found to have enhanced antiviral activity in cell culture studies while also cleaving RSV genomic RNA in an RNase L- and sequence-specific manner. RBI034s efficacy in suppressing RSV replication in cell culture is 50 to 100 times better than ribavirin, the only approved drug for RSV infection. Here we show that the activity of 2 SA antisense compound can be further enhanced by a combination treatment with interferon or ribavirin. The anti-RSV activity resulting from combination treatment is more potent than either treatment alone. We also demonstrate that RBI034 is effective against RSV in three different species: mice, cotton rats, and African green monkeys.
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Affiliation(s)
- Hagen Cramer
- Ridgeway Biosystems, Inc., Cleveland, Ohio, USA.
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13
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Wyde PR, Laquerre S, Chetty SN, Gilbert BE, Nitz TJ, Pevear DC. Antiviral efficacy of VP14637 against respiratory syncytial virus in vitro and in cotton rats following delivery by small droplet aerosol. Antiviral Res 2005; 68:18-26. [PMID: 16112208 DOI: 10.1016/j.antiviral.2005.06.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2005] [Revised: 06/29/2005] [Accepted: 06/29/2005] [Indexed: 10/25/2022]
Abstract
VP14637, the lead compound in a series of substituted bis-tetrazole-benzhydrylphenols developed by ViroPharma Incorporated, was evaluated for antiviral efficacy against respiratory syncytial virus (RSV) in vitro in cell culture and in vivo in cotton rats. A selective index of >3000 (> or =2000 times greater than that observed for ribavirin) was determined in the in vitro studies for this compound against both RSV A and B subtypes. In cotton rats, animals given as little as 126 microg drug/kg by small droplet aerosol in divided doses starting 1 day after experimental virus infection with either a RSV A or B subtype consistently had significantly lower mean pulmonary RSV titers and reduced histopathological findings than mock-treated animals or cotton rats given placebo (vehicle-treated animals). No cotton rat treated with aerosols of VP14637 during these studies manifested any evident untoward responses. Thus, VP14637 exhibited good selective antiviral efficacy both in vitro and in vivo.
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Affiliation(s)
- Philip R Wyde
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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Bolger G, Lapeyre N, Dansereau N, Lagacé L, Berry G, Klosowski K, Mewhort T, Liuzzi M. Primary infection of mice with high titer inoculum respiratory syncytial virus: characterization and response to antiviral therapy. Can J Physiol Pharmacol 2005; 83:198-213. [PMID: 15791294 DOI: 10.1139/y05-007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Intranasal infection of BALB/c mice with respiratory syncytial virus (RSV)-A2 (0.5 x 10(8) - 2.0 x 10(8) plaque-forming units, PFU) produced disease characterized by weight loss (2-3 g) and mortality (60%-100%) with the mean day of death ranging from 6-7 d after infection. The extent of RSV disease was inoculum titer-dependent and required a replication competent virus. Lung titers of virus peaked at 0.5-1 x 10(6) PFU/g wet weight. Bronchoalveolar lavage fluid (BALF) levels of IL-1beta, TNF-alpha, INF-gamma IL-12, IL-6, MIP-1alpha, RANTES, and protein were elevated, whereas IL-2, IL-4, IL-5, IL-13, and IL-10 were unchanged. Histological assessment of lungs revealed marked inflammatory pathology characterized by bronchiolitis, vasculitis, and interstitial pneumonia. Whole-body plethysmography revealed significant disease-associated deficits of respiratory function. Therapy with ribavirin administered either by the intranasal, subcutaneous, or oral route significantly reduced disease in a dose-dependent manner. Delaying the initiation of therapy resulted in a loss of activity for ribavirin. Synagis administered either intramuscularly as a single dose in prophylaxis or intranasally in prophylaxis, followed by therapy, also significantly reduced disease in a dose-dependent manner. Infection of mice with a high titer inoculum of RSV-A2 resulted in severe and fatal pulmonary disease that was responsive to treatment. This model may be useful to characterize the in vivo activity of experimental therapies for RSV infection.
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Affiliation(s)
- Gordon Bolger
- Department of Biological Sciences, Boehringer Ingelheim (Canada) Limited, Research and Development, Laval, Canada.
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15
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Wyde PR, Chetty SN, Timmerman P, Gilbert BE, Andries K. Short duration aerosols of JNJ 2408068 (R170591) administered prophylactically or therapeutically protect cotton rats from experimental respiratory syncytial virus infection. Antiviral Res 2003; 60:221-31. [PMID: 14638398 DOI: 10.1016/j.antiviral.2003.07.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Cotton rats exposed to continuous small droplet aerosols of 2[[2-[[1-(2-aminoethyl)-4-piperidinyl]amino]-4-methyl-1H-benzimidazol-1-yl]methyl]-6-methyl-3-pyridinol (JNJ 2408068) or its hydrochloric salt for only 15 min, one day prior to virus inoculation or one day after, were significantly protected from pulmonary respiratory syncytial virus (RSV) infection compared to control animals similarly infected but exposed to aerosols of placebo at these times. No evidence of toxicity was seen in any of these animals or in cotton rats administered 10 times the minimum cotton rat efficacious dose (i.e. 10x0.39 mg of active compound per kilogram of body weight) for four continuous days. The marked selective antiviral activity observed in the cotton rats mirrored that seen for these compounds in cytotoxicity and antiviral assays performed against RSV in vitro. Plasma kinetics and tissue distribution of JNJ 2408068 in cotton rats following inhalation were determined in separate experiments performed using conditions similar to those utilized in the in vivo efficacy studies. The data from these experiments indicated that significant levels of the test compound were delivered to the lungs of exposed animals, but that extrapulmonary distribution was limited.
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Affiliation(s)
- Philip R Wyde
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
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16
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Hong Z, Cameron CE. Pleiotropic mechanisms of ribavirin antiviral activities. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2003; 59:41-69. [PMID: 12458963 DOI: 10.1007/978-3-0348-8171-5_2] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Renewed interest in the mechanism of action of ribavirin results from its synergistic enhancement of interferon therapy and the need to develop more efficacious agents to treat hepatitis C virus infection. Since the discovery of ribavirin over 30 years ago by scientists at ICN Pharmaceuticals, many mechanisms of action for ribavirin have been proposed. These include inhibition of host inosine monophosphate dehydrogenase by ribavirin monophosphate, inhibition of viral capping enzymes, inhibition of viral RNA synthesis by ribavirin triphosphate, lethal mutagenesis of viral RNA genomes resulting from promiscuous incorporation of ribavirin triphosphate by the viral RNA polymerase, and modulation of the host immune responses. In this article, we will briefly review the evidence for these mechanisms, emphasizing recent findings. In addition, we will discuss strategies for development of nucleoside analogs that may replace ribavirin in the future.
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Affiliation(s)
- Zhi Hong
- Drug Discovery, ICN Pharmaceuticals, Inc., 3300 Hyland Avenue, Costa Mesa, CA 92626, USA
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17
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Wyde PR, Moore-Poveda DK, De Clercq E, Neyts J, Matsuda A, Minakawa N, Guzman E, Gilbert BE. Use of cotton rats to evaluate the efficacy of antivirals in treatment of measles virus infections. Antimicrob Agents Chemother 2000; 44:1146-52. [PMID: 10770743 PMCID: PMC89836 DOI: 10.1128/aac.44.5.1146-1152.2000] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
No practical animal models for the testing of chemotherapeutic or biologic agents identified in cell culture assays as being active against measles virus (MV) are currently available. Cotton rats may serve this purpose. To evaluate this possibility, 5-ethynyl-1-beta-D-ribofuranosylimidazole-4-carboxamide (EICAR) and poly(acrylamidomethyl propanesulfonate) (PAMPS), two compounds that have been reported to inhibit MV in vitro, and ribavirin, an established antiviral drug with MV-inhibitory activity, were evaluated for their antiviral activities against MV and respiratory syncytial virus (RSV) in tissue culture and in hispid cotton rats. A single administration of PAMPS markedly inhibited pulmonary RSV or MV replication (>3 log(10) reduction in pulmonary titer compared to that for controls), but only if this compound was administered intranasally at about the time of virus inoculation. Both EICAR and ribavirin exhibited therapeutic activity against RSV and MV in cotton rats when they were administered parenterally. However, both of these compounds were less effective against MV. On the basis of the pulmonary virus titers on day 4 after virus inoculation, the minimal efficacious dose of EICAR against MV (120 mg/kg of body weight/day when delivered intraperitoneally twice daily) appeared to be three times lower against this virus than that of ribavirin delivered at a similar dose (i.e., 360 mg/kg/day). These findings correlated with those obtained in vitro. The data obtained suggest that cotton rats may indeed be useful for the initial evaluation of the activities of antiviral agents against MV.
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Affiliation(s)
- P R Wyde
- Department of Microbiology and Immunology, Baylor College of Medicine, Houston, Texas 77030, USA.
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18
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Abstract
Billions of people are infected with respiratory viruses annually. Infants and young children, the elderly, immunocompromised individuals and those debilitated by other diseases or nutritional deficiencies are most at risk for serious disease. There are few vaccines available for use against these viruses, and even where there are (influenza, measles and adenovirus), infections remain common. The continued prevalence of respiratory virus infections has lead to renewed efforts to find safe agents effective against the most medically important respiratory viruses: influenza, respiratory syncytial, parainfluenza, measles, rhino- and adenovirus. Copyright 1999 Harcourt Publishers Ltd.
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Affiliation(s)
- Philip R. Wyde
- Department of Microbiology, Immunology, Baylor College of Medicine, Houston, TX, USA
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19
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Sudo K, Watanabe W, Konno K, Sato R, Kajiyashiki T, Shigeta S, Yokota T. Efficacy of RD3-0028 aerosol treatment against respiratory syncytial virus infection in immunosuppressed mice. Antimicrob Agents Chemother 1999; 43:752-7. [PMID: 10103176 PMCID: PMC89202 DOI: 10.1128/aac.43.4.752] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RD3-0028, a benzodithiin compound, has antiviral activity against respiratory syncytial virus (RSV) in cell culture. We used a mouse model of RSV infection to determine the in vivo effect of RD3-0028. Cyclophosphamide (CYP)-treated, immunosuppressed mice were inoculated intranasally. The lungs of the mice were removed on day 4. The virus titers of the lungs of RD3-0028-treated mice were compared to the virus titers of the lungs of virus-inoculated, untreated control mice. In an effort to increase the therapeutic effectiveness of this compound, RD3-0028 was administered by aerosol to RSV-infected mice by using a head-exposure system. Aerosols generated from reservoirs containing RD3-0028 (7 mg/ml) administered for 2 h twice daily for 3 days significantly reduced the pulmonary titer of RSV-infected mice. It is clear that the minimal effective dose of RD3-0028 for RSV-infected mice is significantly less than that of ribavirin, the only compound currently available for use against RSV disease. Furthermore, the RD3-0028 aerosol administration appeared to protect the lungs of infected, CYP-treated mice against tissue damage, as evidenced by the preservation of the lung architecture and a reduction in pulmonary inflammatory infiltrates. RD3-0028 aerosol was not toxic for mice at the therapeutic dose. The present study demonstrates the effectiveness of aerosol administration of RD3-0028 for RSV-infected mice.
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Affiliation(s)
- K Sudo
- Rational Drug Design Laboratory, Fukushima, Japan
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20
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Watanabe W, Sudo K, Sata R, Kajiyashiki T, Konno K, Shigeta S, Yokota T. Novel anti-respiratory syncytial(RS) viral compounds: benzodithiin derivatives. Biochem Biophys Res Commun 1998; 249:922-6. [PMID: 9731237 DOI: 10.1006/bbrc.1998.9222] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Benzodithiin derivatives are highly potent and specific inhibitors of respiratory syncytial virus (RSV) replication in vitro. The most potent and selective congener of a benzodithiin derivative is 1,4-dihydro-2,3-benzodithiin(RD3-0028). According to the modified 3-(4,5-dimethylthiazole-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) assay developed in our laboratories, this compound has a 50% effective concentration of 4.5 microM and a 50% cytotoxic concentration of 271.0 microM, which is superior to that of ribavirin. This compound also inhibits RSV strain subgroups A and B and clinical isolates. RD3-0028, however, does not inhibit the replication of influenza A virus, measles virus, herpes simplex virus types 1 and 2, or human cytomegalovirus. Two other benzodithiin derivatives [1,4-dihydro-6-methyl-2,3-benzodithiin (RD3-0270) and 1,4-dihydro-5-methyl-1-2,3-benzodithiin (RD3-0284)] also inhibit RSV replication at a selectivity index greater a factor of 20. These results suggest that the benzodithiin skeleton is an important structure for inhibitory activity against RSV replication.
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Affiliation(s)
- W Watanabe
- Rational Drug Design Laboratories, Fukushima, Japan
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21
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Abstract
Respiratory syncytial virus (RSV) is a major virus pathogen of infants and young children, an important cause of disease in adults and is responsible for a significant amount of excess morbidity and mortality in the elderly. It also can be devastating in immunosuppressed populations. Vaccines are being developed, but none are currently licensed. Moreover, even if one or more are approved, they may not be suitable for some populations vulnerable to RSV (e.g. very young infants and the immunosuppressed). Ribavirin and immunoglobulin preparations with high titers of RSV-specific neutralizing antibodies are currently approved for use to treat and prevent RSV infection. However, neither of these is cost-effective or simple to administer. New agents are needed to reduce the impact of RSV. This review is concerned with the means currently available for controlling RSV, the search for new agents effective against this virus, and future prospects for preventing and treating RSV infections.
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Affiliation(s)
- P R Wyde
- Department of Microbiology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA.
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22
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de Jong MD, Boucher CA, Cooper DA, Galasso GJ, Gazzard B, Lange JM, Montaner JS, Richman DD, Thomas HC. Summary of the II International Consensus Symposium on Combined Antiviral Therapy and implications for future therapies. Antiviral Res 1997; 35:65-82. [PMID: 9217244 PMCID: PMC7173273 DOI: 10.1016/s0166-3542(97)00020-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- M D de Jong
- Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands.
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23
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Sidwell RW, Huffman JH, Bailey KW, Wong MH, Nimrod A, Panet A. Inhibitory effects of recombinant manganese superoxide dismutase on influenza virus infections in mice. Antimicrob Agents Chemother 1996; 40:2626-31. [PMID: 8913477 PMCID: PMC163588 DOI: 10.1128/aac.40.11.2626] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The oxygen free-radical scavenger recombinant human manganese superoxide dismutase (MnSOD) was studied for its effects on influenza virus infections in mice when used alone and in combination with ribavirin. Mice challenged with influenza A/NWS/33 (H1N1) virus were treated parenterally in doses of 25, 50, and 100 mg/kg of body weight per day every 8 h for 5 days beginning at 48 h post-virus exposure. An increase in mean day to death, lessened decline in arterial oxygen saturation, and reduced lung consolidation and lung virus titers occurred in the treated animals. To determine the influence of viral challenge, experiments were run in which mice were infected with a 100 or 75% lethal dose of virus and were treated intravenously once daily for 5 days beginning 96 h after virus exposure. Weak inhibition of the mortality rate was seen in mice receiving the high viral challenge, whereas significant inhibition occurred in the animals infected with the lower viral challenge, indicating that MnSOD effects are virus dose dependent. To determine if treatment with small-particle aerosol would render an antiviral effect, infected mice were treated by this route for 1 h daily for 5 days beginning 72 h after virus exposure. A dose-responsive disease inhibition was seen. An infection induced by influenza B/Hong Kong/5/72 virus in mice was mildly inhibited by intravenous MnSOD treatment as seen by increased mean day to death, lessened arterial oxygen saturation decline, and lowered lung consolidation. MnSOD was well tolerated in all experiments. A combination of MnSOD and ribavirin, each administered with small-particle aerosol, resulted in a generally mild improvement of the disease induced by the influenza A virus compared with use of either material alone.
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Affiliation(s)
- R W Sidwell
- Institute for Antiviral Research, Utah State University, Logan 84322-5600, USA.
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24
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Perspectives for the chemotherapy of respiratory syncytial virus (RSV) infections. Int J Antimicrob Agents 1996; 7:193-202. [DOI: 10.1016/s0924-8579(96)00319-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/1996] [Indexed: 11/23/2022]
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25
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Gilbert BE, Wyde PR, Wilson SZ, Meyerson LR. SP-303 small-particle aerosol treatment of influenza A virus infection in mice and respiratory syncytial virus infection in cotton rats. Antiviral Res 1993; 21:37-45. [PMID: 8317921 DOI: 10.1016/0166-3542(93)90065-q] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A natural plant product, SP-303, was administered by small-particle aerosol to influenza A/HK virus-infected mice and RSV-infected cotton rats. Aqueous SP-303 at 2 mg/ml in the Collison nebulizer reservoir generated an aerosol with an output of 26 micrograms/l and a particle size distribution of 1.4 microns +/- 4.6 (MMAD +/- GSD). SP-303 at a dosage of 0.5-9.4 mg/kg per day administered for 3-4 days significantly increased both the rate and duration of survival of mice lethally infected with influenza A/HK virus. SP-303 was toxic to mice at 16 mg/kg per day as indicated by weight loss and a decrease in the duration of survival compared to control animals. From these data, a maximum therapeutic index (T.I.) of 12 was calculated. SP-303 given 3-4 days at dosages of 1.3-9.8 mg/kg per day was effective in reducing the pulmonary titer of RSV in infected cotton rats. However, at the 18.7 mg/kg per day dose a significant weight loss compared to control animals was observed; a T.I. of < or = 14 was estimated. These experiments demonstrate that aerosol administration of SP-303 was effective in the treatment of influenza A-infected mice and of RSV-infected cotton rats.
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Affiliation(s)
- B E Gilbert
- Department of Microbiology and Immunology, Baylor College of Medicine, Houston, TX 77030
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