Abstract: International Journal of Antimicrobial Agents 55 (2020) 105938 Contents lists available at ScienceDirect International Journal of Antimicrobial Agents journal homepage: www.elsevier.com/locate/ijantimicag New insights on the antiviral effects of chloroquine against coronavirus: what to expect for COVID-19? Christian A. Devaux a,b,c,∗, Jean-Marc Rolain a,c, Philippe Colson a,c, Didier Raoult a,c a Aix-Marseille Université, IRD, APHM, MEPHI, IHU–Méditerranée Infection, Marseille, France CNRS, Marseille, France c IHU–Méditerranée Infection, 19–21 boulevard Jean Moulin, 13005 Marseille, France b a r t i c l e i n f o Editor: Jose Fernando Oliveira Keywords: COVID-19 SARS-CoV-2 Coronavirus Chloroquine a b s t r a c t Recently, a novel coronavirus (2019-nCoV), officially known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in China. Despite drastic containment measures, the spread of this virus is ongoing. SARS-CoV-2 is the aetiological agent of coronavirus disease 2019 (COVID-19) characterised by pulmonary infection in humans. The efforts of international health authorities have since focused on rapid diagnosis and isolation of patients as well as the search for therapies able to counter the most severe effects of the disease. In the absence of a known efficient therapy and because of the situation of a publichealth emergency, it made sense to investigate the possible effect of chloroquine/hydroxychloroquine against SARS-CoV-2 since this molecule was previously described as a potent inhibitor of most coronaviruses, including SARS-CoV-1. Preliminary trials of chloroquine repurposing in the treatment of COVID19 in China have been encouraging, leading to several new trials. Here we discuss the possible mechanisms of chloroquine interference with the SARS-CoV-2 replication cycle. © 2020 Published by Elsevier B.V.