Abstract: medRxiv preprint doi: https://doi.org/10.1101/2021.06.17.21258639; this version posted June 17, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. Molnupiravir, an Oral Antiviral Treatment for COVID-19 William Fischer, MD, Institute for Global Health and Infectious Disease, Division of Pulmonary Diseases and Critical Care Medicine, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Joseph J. Eron Jr, MD, Department of Medicine, Division of Infectious Diseases, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Wayne Holman, MD, Ridgeback Biotherapeutics LP, Miami, FL, USA. Myron S. Cohen, MD, Institute for Global Health and Infectious Disease, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Lei Fang, MS, Pharstat Inc., Raleigh, NC, USA Laura J. Szewczyk, BS, Ridgeback Biotherapeutics LP, Miami, FL, USA. Timothy P Sheahan, PhD, Department of Epidemiology, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Ralph Baric, Department of Epidemiology, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Katie R. Mollan, MS, Gillings School of Global Public Health, School of Medicine, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Cameron R. Wolfe, MBBS MPH, Department of Medicine, Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USA. 1 NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice. medRxiv preprint doi: https://doi.org/10.1101/2021.06.17.21258639; this version posted June 17, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. Elizabeth R. Duke, MD MA, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, WA, USA. Masoud M. Azizad, MD, Valley Clinical Trials, Inc., Northridge, CA, USA. Katyna Borroto-Esoda, MS, KBE Consulting, Raleigh, NC, USA. David A. Wohl, MD, Institute for Global Health and Infectious Disease, Division of Pulmonary Diseases and Critical Care Medicine, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Amy James Loftis, BSc, Institute for Global Health and Infectious Disease, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Paul Alabanza, BSc, Lineberger Comprehensive Cancer Center, The University of North Carolina and Chapel Hill, Chapel Hill, NC, USA. Felicia Lipansky, Ridgeback Biotherapeutics LP, Miami, FL, USA. Wendy P. Painter, MD MPH, Ridgeback Biotherapeutics LP, Miami, FL, USA. Corresponding author: Wendy P. Painter, MD, MPH, Ridgeback Biotherapeutics, Miami, FL, USA. Abstract Background: Easily distributed oral antivirals are urgently needed to treat coronavirus disease-2019 (COVID-19), prevent progression to severe illness, and block transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We report the results of a 2 medRxiv preprint doi: https://doi.org/10.1101/2021.06.17.21258639; this version posted June 17, 2021. The copyright holder for this preprint (which was not certified by peer review) is the..