Nucleoside analogues for the treatment of coronavirus infections Andrea J Pruijssers1,2 and Mark R Denison1,2,3 Recent outbreaks of SARS-Coronavirus and MERS-Coronavirus (CoV) have heightened awareness about the lack of vaccines or antiviral compounds approved for prevention or treatment of human or potential zoonotic CoVs. Anti-CoV drug development has long been challenged by the activity of a 30 to 50 proofreading exoribonuclease unique to CoVs. Recently, a promising nucleoside analogue with broad-spectrum activity against CoVs has been identified. This review will discuss progress made in the development of antiviral nucleoside and nucleotide analogues targeting viral RNA synthesis as effective therapeutics against CoVinfectionsand proposepromisingstrategies forcombination therapy. Addresses 1 Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, United States 2 Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, TN, United States 3 Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States Corresponding author: Denison, Mark R (