key: cord-270257-5f95gve3 authors: Jeon, Sangeun; Ko, Meehyun; Lee, Jihye; Choi, Inhee; Byun, Soo Young; Park, Soonju; Shum, David; Kim, Seungtaek title: Identification of antiviral drug candidates against SARS-CoV-2 from FDA-approved drugs date: 2020-03-28 journal: bioRxiv DOI: 10.1101/2020.03.20.999730 sha: doc_id: 270257 cord_uid: 5f95gve3 COVID-19 is an emerging infectious disease and was recently declared as a pandemic by WHO. Currently, there is no vaccine or therapeutic available for this disease. Drug repositioning represents the only feasible option to address this global challenge and a panel of 48 FDA-approved drugs that have been pre-selected by an assay of SARS-CoV was screened to identify potential antiviral drug candidates against SARS-CoV-2 infection. We found a total of 24 drugs which exhibited antiviral efficacy (0.1 μM < IC50 < 10 μM) against SARS-CoV-2. In particular, two FDA-approved drugs - niclosamide and ciclesonide – were notable in some respects. These drugs will be tested in an appropriate animal model for their antiviral activities. In near future, these already FDA-approved drugs could be further developed following clinical trials in order to provide additional therapeutic options for patients with COVID-19. COVID-19 is an emerging infectious disease caused by a novel coronavirus, SARS-CoV-2 1 . Although the case fatality rate due to this viral infection varies from 1 to 12% 2 , the transmission rate is relatively high 3 and recently, the WHO declared COVID-19 outbreak a pandemic. Currently, there is no vaccines or therapeutics available and the patients with COVID-19 are being treated with supportive care. Drug repositioning could be an effective strategy to respond immediately to emerging infectious diseases since the new drug development usually takes more than 10 years 4 . FDA-approved drugs provide safe alternatives only in the case where at least modest antiviral activity can be achieved. Accordingly, several drugs are being tested in numerous clinical trials 5 including remdesivir, lopinavir, and chloroquine 6 . In this study, we screened a panel of FDA-approved drugs to identify antiviral drug candidates for the treatment of COVID-19 and suggest the identified drug candidates may be considered for therapeutic development. We screened approximately 3,000 FDA-and IND-approved drug library against SARS-CoV to identify antiviral drug candidates (manuscript in preparation). Since the SARS-CoV and SARS-CoV-2 are very similar (79.5% sequence identity) 1 , the drugs which show antiviral activity against SARS-CoV are expected to show similar extent of antiviral activity against SARS-CoV-2. A total of 35 drugs were selected from the earlier SARS-CoV screening results. In addition, 13 drugs were included based on recommendations from infectious diseases specialists (Table 1) . For screening experiments, Vero cells were used and each drug was added to the cells prior to the virus infection. At 24 h after the infection, the infected cells were scored by immunofluorescence analysis with an antibody specific for the viral N protein of SARS-CoV-2. The confocal microscope images of both viral N protein and cell nuclei were analyzed using our in-house Image Mining (IM) software and the dose-response curve (DRC) for each drug was generated ( Figure 1 ). Chloroquine, lopinavir, and remdesivir were used as reference drugs with IC 50 values of 9.12, 7.28, and 11.41 µM, respectively ( Figure 1A ). Among the 48 drugs that were evaluated in our study, 24 drugs showed potential antiviral activities against SARS-CoV-2 with IC 50 values in Second, ciclesonide is another interesting drug candidate for further development although its antiviral potency was much lower (IC 50 = 4.33 µM) than niclosamide. It is an inhaled corticosteroid used to treat asthma and allergic rhinitis 11 . A recent report by Matsuyama et al. corroborated our finding of ciclesonide as a potential antiviral drug against SARS-CoV-2 12 . A treatment report of three patients who were infected by SARS-CoV-2 in Japan (https://www3.nhk.or.jp/nhkworld/en/news/20200303_20/) warrants further clinical investigation of this drug in patients with COVID-19. Intriguingly, an underlying mechanism for the suppression of viral infection by ciclesonide has been revealed by the isolation of a drug-resistant mutant 12 . The isolation of the drug-resistant mutant indicated that NSP15, a viral riboendonuclease, is the molecular target of ciclesonide. Together, it is not unreasonable to consider that ciclesonide exhibits a direct-acting antiviral activity in addition to its intrinsic antiinflammatory function. In the future, siRNA targeting the hormone receptor will allow to assess the extent of direct-acting antiviral activity. With its proven anti-inflammatory activity, ciclesonide may represent as a potent drug which can manifest dual roles (antiviral and antiinflammatory) for the control of SARS-CoV-2 infection. Prior to our evaluation of 48 drugs against SARS-CoV-2 infection, we also tested antiviral activity of several other drugs based on the cytopathic effect of the virus in the presence of each drug ( Figure 2 ). In particular, the effect of favipiravir and atazanavir was compared to those of the reference drugs (chloroquine, lopinavir, remdesivir) because favipiravir is considered as a drug candidate for clinical trials and atazanavir was recently predicted as the most potent antiviral drug by AI-inference modeling 13 . However, in the current work, we did not observe any antiviral activity of either favipiravir or atazanavir. In summary, we selected and screened 48 FDA-approved drugs based on our SARS-CoV screening and our screening campaign revealed 24 potential antiviral drug candidates against SARS-CoV-2. Our findings could be further validated in an appropriate animal model, and hopefully developed through subsequent clinical trials in order to provide additional therapeutic options for patients with COVID-19. Vero cells were obtained from the American Type Culture Collection (ATCC CCL-81) and Ten-point DRCs were generated for each drug. Vero cells were seeded at 1. Ten-point DRCs were generated for each drug. Vero cells were seeded at 1. A pneumonia outbreak associated with a new coronavirus of probable bat origin Estimating the risk of 2019 Novel Coronavirus death during the course of the outbreak in China Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Infected Pneumonia Drug repositioning: Identifying and developing new uses for existing drugs More than 80 clinical trials launch to test coronavirus treatments Remdesivir and chloroquine effectively inhibit the recently emerged novel coronavirus (2019-nCoV) in vitro Broad Spectrum Antiviral Agent Niclosamide and Its Therapeutic Potential Inhibition of severe acute respiratory syndrome coronavirus replication by niclosamide SKP2 attenuates autophagy through Beclin1-ubiquitination and its inhibition reduces MERS-Coronavirus infection Absorption of pyrvinium pamoate Ciclesonide: A safe and effective inhaled corticosteroid for the treatment of asthma The inhaled corticosteroid ciclesonide blocks coronavirus RNA replication by targeting viral NSP15. bioRxiv (2020) Predicting commercially available antiviral drugs that may act on the novel coronavirus (2019-nCoV) We thank Drs. Wang-Shick Ryu and Spencer Shorte for their helpful discussion and review of the manuscript. The pathogen resource (NCCP43326) for this study was provided by the National Culture Collection for Pathogens. This work was supported by the National Research