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Felicetti T, Sarnari C, Gaito R, Tabarrini O, Manfroni G. Recent Progress toward the Discovery of Small Molecules as Novel Anti-Respiratory Syncytial Virus Agents. J Med Chem 2024; 67:11543-11579. [PMID: 38970494 DOI: 10.1021/acs.jmedchem.4c00630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2024]
Abstract
Respiratory syncytial virus (RSV) stands as the foremost cause of infant hospitalization globally, ranking second only to malaria in terms of infant mortality. Although three vaccines have recently been approved for the prophylaxis of adults aged 60 and above, and pregnant women, there is currently no effective antiviral drug for treating RSV infections. The only preventive measure for infants at high risk of severe RSV disease is passive immunization through monoclonal antibodies. This Perspective offers an overview of the latest advancements in RSV drug discovery of small molecule antivirals, with particular focus on the promising findings from agents targeting the fusion and polymerase proteins. A comprehensive reflection on the current state of RSV research is also given, drawing inspiration from the lessons gleaned from HCV and HIV, while also considering the impact of the recent approval of the three vaccines.
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Affiliation(s)
- Tommaso Felicetti
- Department of Pharmaceutical Sciences, University of Perugia, Via Del Liceo, 1-06123, Perugia, Italy
| | - Chiara Sarnari
- Department of Pharmaceutical Sciences, University of Perugia, Via Del Liceo, 1-06123, Perugia, Italy
| | - Roberta Gaito
- Department of Pharmaceutical Sciences, University of Perugia, Via Del Liceo, 1-06123, Perugia, Italy
| | - Oriana Tabarrini
- Department of Pharmaceutical Sciences, University of Perugia, Via Del Liceo, 1-06123, Perugia, Italy
| | - Giuseppe Manfroni
- Department of Pharmaceutical Sciences, University of Perugia, Via Del Liceo, 1-06123, Perugia, Italy
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2
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Bonneux B, Jacoby E, Ceconi M, Stobbelaar K, Delputte P, Herschke F. Direct-acting antivirals for RSV treatment, a review. Antiviral Res 2024; 229:105948. [PMID: 38972604 DOI: 10.1016/j.antiviral.2024.105948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/20/2024] [Accepted: 06/24/2024] [Indexed: 07/09/2024]
Abstract
Respiratory syncytial virus (RSV) causes respiratory disease and complications in infants, the elderly and the immunocompromised. While three vaccines and two prophylactic monoclonal antibodies are now available, only one antiviral, ribavirin, is currently approved for treatment. This review aims to summarize the current state of treatments directly targeting RSV. Two major viral processes are attractive for RSV-specific antiviral drug discovery and development as they play essential roles in the viral cycle: the entry/fusion process carried out by the fusion protein and the replication/transcription process carried out by the polymerase complex constituted of the L, P, N and M2-1 proteins. For each viral target resistance mutations to small molecules of different chemotypes seem to delineate definite binding pockets in the fusion proteins and in the large proteins. Elucidating the mechanism of action of these inhibitors thus helps to understand how the fusion and polymerase complexes execute their functions. While many inhibitors have been studied, few are currently in clinical development for RSV treatment: one is in phase III, three in phase II and two in phase I. Progression was halted for many others because of strategic decisions, low enrollment, safety, but also lack of efficacy. Lessons can be learnt from the halted programs to increase the success rate of the treatments currently in development.
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Affiliation(s)
- Brecht Bonneux
- Laboratory for Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsbaan 1, 2610, Wilrijk, Belgium; Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Edgar Jacoby
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Martina Ceconi
- Laboratory for Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsbaan 1, 2610, Wilrijk, Belgium
| | - Kim Stobbelaar
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Peter Delputte
- Laboratory for Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsbaan 1, 2610, Wilrijk, Belgium.
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3
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Bonneux B, Shareef A, Tcherniuk S, Anson B, de Bruyn S, Verheyen N, Thys K, Conceição-Neto N, Van Ginderen M, Kwanten L, Ysebaert N, Vranckx L, Peeters E, Lanckacker E, Gallup JM, Sitthicharoenchai P, Alnajjar S, Ackermann MR, Adhikary S, Bhaumik A, Patrick A, Fung A, Sutto-Ortiz P, Decroly E, Mason SW, Lançois D, Deval J, Jin Z, Eléouët JF, Fearns R, Koul A, Roymans D, Rigaux P, Herschke F. JNJ-7184, a respiratory syncytial virus inhibitor targeting the connector domain of the viral polymerase. Antiviral Res 2024; 227:105907. [PMID: 38772503 DOI: 10.1016/j.antiviral.2024.105907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/08/2024] [Accepted: 05/12/2024] [Indexed: 05/23/2024]
Abstract
Respiratory syncytial virus (RSV) can cause pulmonary complications in infants, elderly and immunocompromised patients. While two vaccines and two prophylactic monoclonal antibodies are now available, treatment options are still needed. JNJ-7184 is a non-nucleoside inhibitor of the RSV-Large (L) polymerase, displaying potent inhibition of both RSV-A and -B strains. Resistance selection and hydrogen-deuterium exchange experiments suggest JNJ-7184 binds RSV-L in the connector domain. JNJ-7184 prevents RSV replication and transcription by inhibiting initiation or early elongation. JNJ-7184 is effective in air-liquid interface cultures and therapeutically in neonatal lambs, acting to drastically reverse the appearance of lung pathology.
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Affiliation(s)
- Brecht Bonneux
- Laboratory for Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsbaan 1, 2610 Wilrijk, Belgium; Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Afzaal Shareef
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA 02118, USA
| | - Sergey Tcherniuk
- Unité de Virologie et Immunologie Moléculaires (VIM, UMR892), INRAE, Université Paris-Saclay, 78352 Jouy-en-Josas, France
| | - Brandon Anson
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Suzanne de Bruyn
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Nick Verheyen
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Kim Thys
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | | | | | - Leen Kwanten
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Nina Ysebaert
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Luc Vranckx
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Elien Peeters
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Ellen Lanckacker
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | | | | | | | | | - Suraj Adhikary
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Anusarka Bhaumik
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Aaron Patrick
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Amy Fung
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Priscila Sutto-Ortiz
- AFMB, Aix-Marseille University, CNRS UMR 7257, 163 Avenue de Luminy, Marseille, France
| | - Etienne Decroly
- AFMB, Aix-Marseille University, CNRS UMR 7257, 163 Avenue de Luminy, Marseille, France
| | - Stephen W Mason
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | | | - Jerome Deval
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Zhinan Jin
- Janssen Research & Development LLC, Spring House (PA 19477) And Brisbane (CA 94005), USA
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires (VIM, UMR892), INRAE, Université Paris-Saclay, 78352 Jouy-en-Josas, France
| | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA 02118, USA
| | - Anil Koul
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium.
| | - Dirk Roymans
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Peter Rigaux
- Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium
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4
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Zou G, Cao S, Gao Z, Yie J, Wu JZ. Current state and challenges in respiratory syncytial virus drug discovery and development. Antiviral Res 2024; 221:105791. [PMID: 38160942 DOI: 10.1016/j.antiviral.2023.105791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/22/2023] [Accepted: 12/23/2023] [Indexed: 01/03/2024]
Abstract
Human respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections (LRTI) in young children and elderly people worldwide. Recent significant progress in our understanding of the structure and function of RSV proteins has led to the discovery of several clinical candidates targeting RSV fusion and replication. These include both the development of novel small molecule interventions and the isolation of potent monoclonal antibodies. In this review, we summarize the state-of-the-art of RSV drug discovery, with a focus on the characteristics of the candidates that reached the clinical stage of development. We also discuss the lessons learned from failed and discontinued clinical developments and highlight the challenges that remain for development of RSV therapies.
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Affiliation(s)
- Gang Zou
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China.
| | - Sushan Cao
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Zhao Gao
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Junming Yie
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Jim Zhen Wu
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
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Cox RM, Plemper RK. Design and Execution of In Vitro Polymerase Assays for Measles Virus and Related Mononegaviruses. Methods Mol Biol 2024; 2808:19-33. [PMID: 38743360 DOI: 10.1007/978-1-0716-3870-5_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Morbilliviruses such as measles virus (MeV) are responsible for major morbidity and mortality worldwide, despite the availability of an effective vaccine and global vaccination campaigns. MeV belongs to the mononegavirus order of viral pathogens that store their genetic information in non-segmented negative polarity RNA genomes. Genome replication and viral gene expression are carried out by a virus-encoded RNA-dependent RNA polymerase (RdRP) complex that has no immediate host cell analog. To better understand the organization and regulation of the viral RdRP and mechanistically characterize antiviral candidates, biochemical RdRP assays have been developed that employ purified recombinant polymerase complexes and synthetic RNA templates to monitor the initiation of RNA synthesis and RNA elongation in vitro. In this article, we will discuss strategies for the efficient expression and preparation of mononegavirus polymerase complexes, provide detailed protocols for the execution and optimization of RdRP assays, evaluate alternative options for the choice of template and detection system, and describe the application of the assay for the characterization of inhibitor candidates. Although MeV RdRP assays are the focus of this article, the general strategies and experimental approaches are readily transferable to related viruses in the mononegavirus order.
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Affiliation(s)
- Robert M Cox
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA
| | - Richard K Plemper
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA.
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Yu X, Abeywickrema P, Bonneux B, Behera I, Anson B, Jacoby E, Fung A, Adhikary S, Bhaumik A, Carbajo RJ, De Bruyn S, Miller R, Patrick A, Pham Q, Piassek M, Verheyen N, Shareef A, Sutto-Ortiz P, Ysebaert N, Van Vlijmen H, Jonckers THM, Herschke F, McLellan JS, Decroly E, Fearns R, Grosse S, Roymans D, Sharma S, Rigaux P, Jin Z. Structural and mechanistic insights into the inhibition of respiratory syncytial virus polymerase by a non-nucleoside inhibitor. Commun Biol 2023; 6:1074. [PMID: 37865687 PMCID: PMC10590419 DOI: 10.1038/s42003-023-05451-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 10/11/2023] [Indexed: 10/23/2023] Open
Abstract
The respiratory syncytial virus polymerase complex, consisting of the polymerase (L) and phosphoprotein (P), catalyzes nucleotide polymerization, cap addition, and cap methylation via the RNA dependent RNA polymerase, capping, and Methyltransferase domains on L. Several nucleoside and non-nucleoside inhibitors have been reported to inhibit this polymerase complex, but the structural details of the exact inhibitor-polymerase interactions have been lacking. Here, we report a non-nucleoside inhibitor JNJ-8003 with sub-nanomolar inhibition potency in both antiviral and polymerase assays. Our 2.9 Å resolution cryo-EM structure revealed that JNJ-8003 binds to an induced-fit pocket on the capping domain, with multiple interactions consistent with its tight binding and resistance mutation profile. The minigenome and gel-based de novo RNA synthesis and primer extension assays demonstrated that JNJ-8003 inhibited nucleotide polymerization at the early stages of RNA transcription and replication. Our results support that JNJ-8003 binding modulates a functional interplay between the capping and RdRp domains, and this molecular insight could accelerate the design of broad-spectrum antiviral drugs.
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Affiliation(s)
- Xiaodi Yu
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA.
| | - Pravien Abeywickrema
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Brecht Bonneux
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
- University of Antwerp, Antwerp, Belgium
| | - Ishani Behera
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Brandon Anson
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Edgar Jacoby
- Johnson & Johnson Innovative Medicine, Beerse, Belgium
| | - Amy Fung
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Suraj Adhikary
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Anusarka Bhaumik
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Rodrigo J Carbajo
- Johnson & Johnson Innovative Medicine, Janssen-Cilag, Discovery Chemistry S.A. Río Jarama, 75A, 45007, Toledo, Spain
| | | | - Robyn Miller
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Aaron Patrick
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Quyen Pham
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Madison Piassek
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Nick Verheyen
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Afzaal Shareef
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, 02118, USA
| | | | - Nina Ysebaert
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | | | | | | | - Jason S McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB, UMR 7257, Marseille, France
| | - Rachel Fearns
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, 02118, USA
| | | | - Dirk Roymans
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Sujata Sharma
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Peter Rigaux
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Zhinan Jin
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA.
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Abstract
The nonsegmented, negative-strand RNA viruses (nsNSVs), also known as the order Mononegavirales, have a genome consisting of a single strand of negative-sense RNA. Integral to the nsNSV replication cycle is the viral polymerase, which is responsible for transcribing the viral genome, to produce an array of capped and polyadenylated messenger RNAs, and replicating it to produce new genomes. To perform the different steps that are necessary for these processes, the nsNSV polymerases undergo a series of coordinated conformational transitions. While much is still to be learned regarding the intersection of nsNSV polymerase dynamics, structure, and function, recently published polymerase structures, combined with a history of biochemical and molecular biology studies, have provided new insights into how nsNSV polymerases function as dynamic machines. In this review, we consider each of the steps involved in nsNSV transcription and replication and suggest how these relate to solved polymerase structures.
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Affiliation(s)
- Mohamed Ouizougun-Oubari
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA;
| | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA;
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Kleiner VA, O Fischmann T, Howe JA, Beshore DC, Eddins MJ, Hou Y, Mayhood T, Klein D, Nahas DD, Lucas BJ, Xi H, Murray E, Ma DY, Getty K, Fearns R. Conserved allosteric inhibitory site on the respiratory syncytial virus and human metapneumovirus RNA-dependent RNA polymerases. Commun Biol 2023; 6:649. [PMID: 37337079 DOI: 10.1038/s42003-023-04990-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/26/2023] [Indexed: 06/21/2023] Open
Abstract
Respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) are related RNA viruses responsible for severe respiratory infections and resulting disease in infants, elderly, and immunocompromised adults1-3. Therapeutic small molecule inhibitors that bind to the RSV polymerase and inhibit viral replication are being developed, but their binding sites and molecular mechanisms of action remain largely unknown4. Here we report a conserved allosteric inhibitory site identified on the L polymerase proteins of RSV and HMPV that can be targeted by a dual-specificity, non-nucleoside inhibitor, termed MRK-1. Cryo-EM structures of the inhibitor in complexes with truncated RSV and full-length HMPV polymerase proteins provide a structural understanding of how MRK-1 is active against both viruses. Functional analyses indicate that MRK-1 inhibits conformational changes necessary for the polymerase to engage in RNA synthesis initiation and to transition into an elongation mode. Competition studies reveal that the MRK-1 binding pocket is distinct from that of a capping inhibitor with an overlapping resistance profile, suggesting that the polymerase conformation bound by MRK-1 may be distinct from that involved in mRNA capping. These findings should facilitate optimization of dual RSV and HMPV replication inhibitors and provide insights into the molecular mechanisms underlying their polymerase activities.
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Affiliation(s)
- Victoria A Kleiner
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA
| | | | | | | | | | - Yan Hou
- MRL, Merck & Co., Inc., Rahway, NJ, USA
| | | | | | | | | | - He Xi
- MRL, Merck & Co., Inc., Rahway, NJ, USA
| | | | | | | | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA.
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Sutto-Ortiz P, Eléouët JF, Ferron F, Decroly E. Biochemistry of the Respiratory Syncytial Virus L Protein Embedding RNA Polymerase and Capping Activities. Viruses 2023; 15:v15020341. [PMID: 36851554 PMCID: PMC9960070 DOI: 10.3390/v15020341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/12/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023] Open
Abstract
The human respiratory syncytial virus (RSV) is a negative-sense, single-stranded RNA virus. It is the major cause of severe acute lower respiratory tract infection in infants, the elderly population, and immunocompromised individuals. There is still no approved vaccine or antiviral treatment against RSV disease, but new monoclonal prophylactic antibodies are yet to be commercialized, and clinical trials are in progress. Hence, urgent efforts are needed to develop efficient therapeutic treatments. RSV RNA synthesis comprises viral transcription and replication that are catalyzed by the large protein (L) in coordination with the phosphoprotein polymerase cofactor (P), the nucleoprotein (N), and the M2-1 transcription factor. The replication/transcription is orchestrated by the L protein, which contains three conserved enzymatic domains: the RNA-dependent RNA polymerase (RdRp), the polyribonucleotidyl transferase (PRNTase or capping), and the methyltransferase (MTase) domain. These activities are essential for the RSV replicative cycle and are thus considered as attractive targets for the development of therapeutic agents. In this review, we summarize recent findings about RSV L domains structure that highlight how the enzymatic activities of RSV L domains are interconnected, discuss the most relevant and recent antivirals developments that target the replication/transcription complex, and conclude with a perspective on identified knowledge gaps that enable new research directions.
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Affiliation(s)
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, F78350 Jouy en Josas, France
| | - François Ferron
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- European Virus Bioinformatics Center, Leutragraben 1, 07743 Jena, Germany
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- Correspondence:
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