Small-molecule inhibition of SARS-CoV-2 NSP14 RNA cap methyltransferase
- Nature. 2024 Dec 11. doi: 10.1038/s41586-024-08320-0.
- 1. Laboratory for RNA Molecular Biology, The Rockefeller University, New York, NY, USA.
- 2. Sanders Tri-Institutional Therapeutics Discovery Institute, The Rockefeller University, New York, NY, USA.
- 3. Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY, USA.
- 4. Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY, USA.
- 5. Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA.
- 6. Department of Medicine, Division of Infectious Diseases, Columbia University, New York, NY, USA.
- 7. Fisher Drug Discovery Resource Center, The Rockefeller University, New York, NY, USA.
- 8. PROTEROS Biostructures GmbH, Planegg-Martinsried, Germany.
- 9. Proteomics Resource Center, The Rockefeller University, New York, NY, USA.
- 10. Laboratory for RNA Molecular Biology, The Rockefeller University, New York, NY, USA. [email protected].
Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)1. The rapid development of highly effective vaccines2,3 against SARS-CoV-2 has altered the trajectory of the pandemic, and Antiviral therapeutics4 have further reduced the number of COVID-19 hospitalizations and deaths. Coronaviruses are enveloped, positive-sense, single-stranded RNA viruses that encode various structural and non-structural proteins, including those critical for viral RNA replication and evasion from innate immunity5. Here we report the discovery and development of a first-in-class non-covalent small-molecule inhibitor of the viral guanine-N7 methyltransferase (MTase) NSP14. High-throughput screening identified RU-0415529, which inhibited SARS-CoV-2 NSP14 by forming a unique ternary S-adenosylhomocysteine (SAH)-bound complex. Hit-to-lead optimization of RU-0415529 resulted in TDI-015051 with a dissociation constant (Kd) of 61 pM and a half-maximal effective concentration (EC50) of 11 nM, inhibiting virus Infection in a cell-based system. TDI-015051 also inhibited viral replication in primary small airway epithelial cells and in a transgenic mouse model of SARS CoV-2 Infection with an efficacy comparable with the FDA-approved reversible covalent protease inhibitor nirmatrelvir6. The inhibition of viral cap methylases as an Antiviral strategy is also adaptable to Other pandemic viruses.