1
|
Cruz JS, de Souza Luna LK, Alves VRG, Conte DD, Bellei NCJ. Viral load of respiratory syncytial virus among children from primary care and hospital settings admitted to a university hospital in Brazil (2009-2013). J Med Virol 2021; 93:3397-3400. [PMID: 32543739 DOI: 10.1002/jmv.26185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/08/2020] [Accepted: 06/14/2020] [Indexed: 11/09/2022]
Abstract
Respiratory syncytial virus (RSV) is a relevant cause of acute respiratory infection among children. Viral replication and immune conditions may account for severity. RSV viral load (VL) was assessed in 486 children (290 hospitalized and 196 from primary care) attended at São Paulo Hospital from 2009 to 2013. VL was calculated by real-time reverse transcription-polymerase chain reaction and expressed in Log10 RNA copies/mL. Coinfection with rhinovirus (RV) and influenza A virus was also tested. Young children (<1 year of age) had a higher mean VL than older children at primary care (6.35 and 4.34 Log10 RNA copies/mL, respectively; P = .0006). Conversely, hospitalized children ≥2 years of age, presented higher mean VL compared with the same age children of primary care (6.10 and 4.26, respectively; P = .0024). RV was the most codetected virus in RSV positive patients (20% from primary care and 14% in hospitalized), and influenza A virus was found in 11% of primary care and 0.4% in hospitalized children with RSV, without RSV VL association (P = .2903). These findings may guide future therapies and immunization policies considering the role of viral load on clinical presentation among older hospitalized children and also the change of infection transmissions.
Collapse
Affiliation(s)
- Jéssica Santiago Cruz
- Clinical Virology Laboratory, Infectious Diseases Unit, Medicine Department, São Paulo Federal University, São Paulo, Brazil
| | - Luciano Kleber de Souza Luna
- Clinical Virology Laboratory, Infectious Diseases Unit, Medicine Department, São Paulo Federal University, São Paulo, Brazil
| | | | - Danielle Dias Conte
- Clinical Virology Laboratory, Infectious Diseases Unit, Medicine Department, São Paulo Federal University, São Paulo, Brazil
| | - Nancy Cristina Junqueira Bellei
- Clinical Virology Laboratory, Infectious Diseases Unit, Medicine Department, São Paulo Federal University, São Paulo, Brazil
| |
Collapse
|
2
|
Discovery of a Novel Respiratory Syncytial Virus Replication Inhibitor. Antimicrob Agents Chemother 2021; 65:AAC.02576-20. [PMID: 33782012 PMCID: PMC8316115 DOI: 10.1128/aac.02576-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/18/2021] [Indexed: 11/20/2022] Open
Abstract
A high-throughput screen of a Roche internal chemical library based on inhibition of the respiratory syncytial virus (RSV)-induced cytopathic effect (CPE) on HEp-2 cells was performed to identify RSV inhibitors. Over 2,000 hits were identified and confirmed to be efficacious against RSV infection in vitro Here, we report the discovery of a triazole-oxadiazole derivative, designated triazole-1, as an RSV replication inhibitor, and we characterize its mechanism of action. Triazole-1 inhibited the replication of both RSV A and B subtypes with 50% inhibitory concentration (IC50) values of approximately 1 μM, but it was not effective against other viruses, including influenza virus A, human enterovirus 71 (EV71), and vaccinia virus. Triazole-1 was shown to inhibit RSV replication when added at up to 8 h after viral entry, suggesting that it inhibits RSV after viral entry. In a minigenome reporter assay in which RSV transcription regulatory sequences flanking a luciferase gene were cotransfected with RSV N/P/L/M2-1 genes into HEp-2 cells, triazole-1 demonstrated specific and dose-dependent RSV transcription inhibitory effects. Consistent with these findings, deep sequencing of the genomes of triazole-1-resistant mutants revealed a single point mutation (A to G) at nucleotide 13546 of the RSV genome, leading to a T-to-A change at amino acid position 1684 of the L protein, which is the RSV RNA polymerase for both viral transcription and replication. The effect of triazole-1 on minigenome transcription, which was mediated by the L protein containing the T1684A mutation, was significantly reduced, suggesting that the T1684A mutation alone conferred viral resistance to triazole-1.
Collapse
|
3
|
Orally Efficacious Broad-Spectrum Ribonucleoside Analog Inhibitor of Influenza and Respiratory Syncytial Viruses. Antimicrob Agents Chemother 2018; 62:AAC.00766-18. [PMID: 29891600 DOI: 10.1128/aac.00766-18] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 05/31/2018] [Indexed: 01/29/2023] Open
Abstract
Morbidity and mortality resulting from influenza-like disease are a threat, especially for older adults. To improve case management, next-generation broad-spectrum antiviral therapeutics that are efficacious against major drivers of influenza-like disease, including influenza viruses and respiratory syncytial virus (RSV), are urgently needed. Using a dual-pathogen high-throughput screening protocol for influenza A virus (IAV) and RSV inhibitors, we have identified N4-hydroxycytidine (NHC) as a potent inhibitor of RSV, influenza B viruses, and IAVs of human, avian, and swine origins. Biochemical in vitro polymerase assays and viral RNA sequencing revealed that the ribonucleotide analog is incorporated into nascent viral RNAs in place of cytidine, increasing the frequency of viral mutagenesis. Viral passaging in cell culture in the presence of an inhibitor did not induce robust resistance. Pharmacokinetic profiling demonstrated dose-dependent oral bioavailability of 36 to 56%, sustained levels of the active 5'-triphosphate anabolite in primary human airway cells and mouse lung tissue, and good tolerability after extended dosing at 800 mg/kg of body weight/day. The compound was orally efficacious against RSV and both seasonal and highly pathogenic avian IAVs in mouse models, reducing lung virus loads and alleviating disease biomarkers. Oral dosing reduced IAV burdens in a guinea pig transmission model and suppressed virus spread to uninfected contact animals through direct transmission. Based on its broad-spectrum efficacy and pharmacokinetic properties, NHC is a promising candidate for future clinical development as a treatment option for influenza-like diseases.
Collapse
|
4
|
Simões EAF, Bont L, Manzoni P, Fauroux B, Paes B, Figueras-Aloy J, Checchia PA, Carbonell-Estrany X. Past, Present and Future Approaches to the Prevention and Treatment of Respiratory Syncytial Virus Infection in Children. Infect Dis Ther 2018; 7:87-120. [PMID: 29470837 PMCID: PMC5840107 DOI: 10.1007/s40121-018-0188-z] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Indexed: 12/27/2022] Open
Abstract
INTRODUCTION The REGAL (RSV Evidence - A Geographical Archive of the Literature) series has provided a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This seventh and final publication covers the past, present and future approaches to the prevention and treatment of RSV infection among infants and children. METHODS A systematic review was undertaken of publications between January 1, 1995 and December 31, 2017 across PubMed, Embase and The Cochrane Library. Studies reporting data on the effectiveness and tolerability of prophylactic and therapeutic agents for RSV infection were included. Study quality and strength of evidence (SOE) were graded using recognized criteria. A further nonsystematic search of the published literature and Clinicaltrials.gov on antiviral therapies and RSV vaccines currently in development was also undertaken. RESULTS The systematic review identified 1441 studies of which 161 were included. Management of RSV remains centered around prophylaxis with the monoclonal antibody palivizumab, which has proven effective in reducing RSV hospitalization (RSVH) in preterm infants < 36 weeks' gestational age (72% reduction), children with bronchopulmonary dysplasia (65% reduction), and infants with hemodynamically significant congenital heart disease (53% reduction) (high SOE). Palivizumab has also shown to be effective in reducing recurrent wheezing following RSVH (high SOE). Treatment of RSV with ribavirin has conflicting success (moderate SOE). Antibodies with increased potency and extended half-life are currently entering phase 3 trials. There are approximately 15 RSV vaccines in clinical development targeting the infant directly or indirectly via the mother. CONCLUSION Palivizumab remains the only product licensed for RSV prophylaxis, and only available for high-risk infants. For the general population, there are several promising vaccines and monoclonal antibodies in various stages of clinical development, with the aim to significantly reduce the global healthcare impact of this common viral infection. FUNDING AbbVie.
Collapse
Affiliation(s)
- Eric A F Simões
- Center for Global Health, Colorado School of Public Health, University of Colorado School of Medicine, Aurora, CO, USA
| | - Louis Bont
- University Medical Center Utrecht, Utrecht, The Netherlands
- ReSViNET (Respiratory Syncytial Virus Network), Utrecht, The Netherlands
| | - Paolo Manzoni
- ReSViNET (Respiratory Syncytial Virus Network), Utrecht, The Netherlands
- Neonatology and NICU, Sant'Anna Hospital, Turin, Italy
| | - Brigitte Fauroux
- Necker University Hospital and Paris 5 University, Paris, France
| | - Bosco Paes
- Department of Paediatrics (Neonatal Division), McMaster University, Hamilton, Canada
| | - Josep Figueras-Aloy
- Hospital Clínic, Catedràtic de Pediatria, Universitat de Barcelona, Barcelona, Spain
| | - Paul A Checchia
- Baylor College of Medicine, Texas Children's Hospital Houston, Houston, TX, USA
| | - Xavier Carbonell-Estrany
- Hospital Clinic, Institut d'Investigacions Biomediques August Pi Suñer (IDIBAPS), Barcelona, Spain.
| |
Collapse
|
5
|
Fearns R, Plemper RK. Polymerases of paramyxoviruses and pneumoviruses. Virus Res 2017; 234:87-102. [PMID: 28104450 DOI: 10.1016/j.virusres.2017.01.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Revised: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 11/13/2022]
Abstract
The paramyxo- and pneumoviruses are members of the order Mononegavirales, a group of viruses with non-segmented, negative strand RNA genomes. The polymerases of these viruses are multi-functional complexes, capable of transcribing subgenomic capped and polyadenylated mRNAs and replicating the genome. Although there is no native structure available for any complete paramyxo- or pneumovirus polymerase, functional and structural studies of a fragment of a pneumovirus polymerase protein and mutation analyses and resistance profiling of small-molecule inhibitors have generated a wealth of mechanistic information. This review integrates these data with the structure of a related polymerase, identifying similarities, differences, gaps in knowledge, and avenues for antiviral drug development.
Collapse
Affiliation(s)
- Rachel Fearns
- Department of Microbiology, Boston University School of Medicine, Boston, MA 02118, United States.
| | - Richard K Plemper
- Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, United States
| |
Collapse
|
6
|
Drysdale SB, Green CA, Sande CJ. Best practice in the prevention and management of paediatric respiratory syncytial virus infection. Ther Adv Infect Dis 2016; 3:63-71. [PMID: 27034777 PMCID: PMC4784570 DOI: 10.1177/2049936116630243] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Respiratory syncytial virus (RSV) infection is ubiquitous with almost all infants having been infected by 2 years of age and lifelong repeated infections common. It is the second largest cause of mortality, after malaria, in infants outside the neonatal period and causes up to 200,000 deaths per year worldwide. RSV results in clinical syndromes that include upper respiratory tract infections, otitis media, bronchiolitis (up to 80% of cases) and lower respiratory tract disease including pneumonia and exacerbations of asthma or viral-induced wheeze. For the purposes of this review we will focus on RSV bronchiolitis in infants in whom the greatest disease burden lies. For infants requiring hospital admission, the identification of the causative respiratory virus is used to direct cohorting or isolation and infection control procedures to minimize nosocomial transmission. Nosocomial RSV infections are associated with poorer clinical outcomes, including increased mortality, the need for mechanical ventilation and longer length of hospital stay. Numerous clinical guidelines for the management of infants with bronchiolitis have been published, although none are specific for RSV bronchiolitis. Ribavirin is the only licensed drug for the specific treatment of RSV infection but due to drug toxicity and minimal clinical benefit it has not been recommended for routine clinical use. There is currently no licensed vaccine to prevent RSV infection but passive immunoprophylaxis using a monoclonal antibody, palivizumab, reduces the risk of hospitalization due to RSV infection by 39-78% in various high-risk infants predisposed to developing severe RSV disease. The current management of RSV bronchiolitis is purely supportive, with feeding support and oxygen supplementation until the infant immune system mounts a response capable of controlling the disease. The development of a successful treatment or prophylactic agent has the potential to revolutionize the care and outcome for severe RSV infections in the world's most vulnerable infants.
Collapse
|
7
|
Broadbent L, Groves H, Shields MD, Power UF. Respiratory syncytial virus, an ongoing medical dilemma: an expert commentary on respiratory syncytial virus prophylactic and therapeutic pharmaceuticals currently in clinical trials. Influenza Other Respir Viruses 2016; 9:169-78. [PMID: 25847510 PMCID: PMC4474493 DOI: 10.1111/irv.12313] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2015] [Indexed: 12/30/2022] Open
Abstract
As the most important viral cause of severe respiratory disease in infants and increasing recognition as important in the elderly and immunocompromised, respiratory syncytial virus (RSV) is responsible for a massive health burden worldwide. Prophylactic antibodies were successfully developed against RSV. However, their use is restricted to a small group of infants considered at high risk of severe RSV disease. There is still no specific therapeutics or vaccines to combat RSV. As such, it remains a major unmet medical need for most individuals. The World Health Organisations International Clinical Trials Registry Platform (WHO ICTRP) and PubMed were used to identify and review all RSV vaccine, prophylactic and therapeutic candidates currently in clinical trials. This review presents an expert commentary on all RSV-specific prophylactic and therapeutic candidates that have entered clinical trials since 2008.
Collapse
Affiliation(s)
- Lindsay Broadbent
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Helen Groves
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Michael D Shields
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, UK.,The Royal Belfast Hospital for Sick Children, Belfast, UK
| | - Ultan F Power
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, UK
| |
Collapse
|
8
|
Wang G, Deval J, Hong J, Dyatkina N, Prhavc M, Taylor J, Fung A, Jin Z, Stevens SK, Serebryany V, Liu J, Zhang Q, Tam Y, Chanda SM, Smith DB, Symons JA, Blatt LM, Beigelman L. Discovery of 4'-chloromethyl-2'-deoxy-3',5'-di-O-isobutyryl-2'-fluorocytidine (ALS-8176), a first-in-class RSV polymerase inhibitor for treatment of human respiratory syncytial virus infection. J Med Chem 2015; 58:1862-78. [PMID: 25667954 DOI: 10.1021/jm5017279] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Respiratory syncytial virus (RSV) is a leading pathogen of childhood and is associated with significant morbidity and mortality. To date, ribavirin is the only approved small molecule drug, which has limited use. The only other RSV drug is palivizumab, a monoclonal antibody, which is used for RSV prophylaxis. Clearly, there is an urgent need for small molecule RSV drugs. This article reports the design, synthesis, anti-RSV activity, metabolism, and pharmacokinetics of a series of 4'-substituted cytidine nucleosides. Among tested compounds 4'-chloromethyl-2'-deoxy-2'-fluorocytidine (2c) exhibited the most promising activity in the RSV replicon assay with an EC50 of 0.15 μM. The 5'-triphosphate of 2c (2c-TP) inhibited RSV polymerase with an IC50 of 0.02 μM without appreciable inhibition of human DNA and RNA polymerases at 100 μM. ALS-8176 (71), the 3',5'-di-O-isobutyryl prodrug of 2c, demonstrated good oral bioavailability and a high level of 2c-TP in vivo. Compound 71 is a first-in-class nucleoside RSV polymerase inhibitor that demonstrated excellent anti-RSV efficacy and safety in a phase 2 clinical RSV challenge study.
Collapse
Affiliation(s)
- Guangyi Wang
- Alios BioPharma, Inc. , 260 East Grand Avenue, South San Francisco, California 94080, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|