Drug Res (Stuttg) 2021; 71(03): 166-170
DOI: 10.1055/a-1296-7935
Opinion Paper

Favipiravir and COVID-19: A Simplified Summary

1   Department of Pharmacology and Toxicology, Faculty of Pharmacy, Urmia University of Medical Sciences, Urmia, Iran
Sarvin Pashapour
2   Department of Pediatrics, Faculty of Medicine, Motahari Hospital, Urmia University of Medical Sciences, Urmia, Iran
› Author Affiliations


A recent outbreak of coronavirus disease 2019 (COVID-19) caused by the novel coronavirus designated as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) started in Wuhan, China, at the end of 2019 and then spread rapidly all over the world. However, there are no specific antiviral therapies for COVID-19, using the agents which approved or in development for other viral infections is one of the potentially quickest ways to find treatment for this new viral infection. Favipiravir is an effective agent that acts as a nucleotide analog that selectively inhibits the viral RNA dependent RNA polymerase or causes lethal mutagenesis upon incorporation into the virus RNA. In view of recent studies and discussion on favipiravir, in this mini review we aimed to summarize the clinical trials studying the efficacy and safety of favipiravir in patients with COVID-19.

Publication History

Received: 16 September 2020

Accepted: 20 October 2020

Article published online:
11 November 2020

© 2020. Thieme. All rights reserved.

Georg Thieme Verlag KG
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  • References

  • 1 Ai J-W et al. Optimizing diagnostic strategy for novel coronavirus pneumonia, a multi-center study in Eastern China. medRxiv 2020; 2020.02.13.20022673
  • 2 Lai C-C. et al. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and corona virus disease-2019 (COVID-19): The epidemic and the challenges. International Journal of Antimicrobial Agents 2020; 105924
  • 3 Sohrabi C et al. World Health Organization declares global emergency: A review of the 2019 novel coronavirus (COVID-19). International Journal of Surgery 2020; 76: 71–76
  • 4 Wang D et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus–infected pneumonia in Wuhan, China. Jama 2020; 323: 1061–1069
  • 5 Zhang Jj et al. Clinical characteristics of 140 patients infected by SARS-CoV-2 in Wuhan, China. Allergy 2020; 75: 1730–1741
  • 6 Yao TT et al. A Systematic Review of Lopinavir Therapy for SARS Coronavirus and MERS Coronavirus-A Possible Reference for Coronavirus Disease-19 Treatment Option. Journal of Medical Virology 2020; 92: 556–561
  • 7 Cai Q et al. Experimental Treatment with Favipiravir for COVID-19: An Open-Label Control Study. Engineering 2020; https://10.1016/j.eng.2020.03.007. Online ahead of print.
  • 8 Li G, De Clercq E. Therapeutic options for the 2019 novel coronavirus (2019-nCoV). 2020, Nature Publishing Group
  • 9 Furuta Y. et al. In vitro and in vivo activities of anti-influenza virus compound T-705. Antimicrobial Agents and Chemotherapy 2002; 46: 977-981
  • 10 Dong L, Hu S, Gao J. Discovering drugs to treat coronavirus disease 2019 (COVID-19). Drug Discoveries & Therapeutics 2020; 14: 58-60
  • 11 Baranovich T. et al. T-705 (favipiravir) induces lethal mutagenesis in influenza A H1N1 viruses in vitro. Journal of Virology 2013; 87: 3741-3751
  • 12 Furuta Y. et al. Mechanism of action of T-705 against influenza virus. Antimicrobial Agents and Chemotherapy 2005; 49: 981-986
  • 13 Jin Z. et al. The ambiguous base-pairing and high substrate efficiency of T-705 (favipiravir) ribofuranosyl 5′-triphosphate towards influenza A virus polymerase. PLoS One 2013; 8: e68347
  • 14 Smee DF. et al. Intracellular metabolism of favipiravir (T-705) in uninfected and influenza A (H5N1) virus-infected cells. Journal of Antimicrobial Chemotherapy 2009; 64: 741-746
  • 15 Vanderlinden E. et al. Distinct effects of T-705 (favipiravir) and ribavirin on influenza virus replication and viral RNA synthesis. Antimicrobial Agents and Chemotherapy 2016; 60: 6679-6691
  • 16 Furuta Y, Komeno T, Nakamura T. Favipiravir (T-705), a broad spectrum inhibitor of viral RNA polymerase. Proceedings of the Japan Academy, Series B 2017; 93: 449-463
  • 17 Gowen BB. et al. In vitro and in vivo activities of T-705 against arenavirus and bunyavirus infections. Antimicrobial Agents and Chemotherapy 2007; 51: 3168-3176
  • 18 Safronetz D. et al. The broad-spectrum antiviral favipiravir protects guinea pigs from lethal Lassa virus infection post-disease onset. Scientific Reports 2015; 5: 14775
  • 19 Rocha-Pereira J. et al. Favipiravir (T-705) inhibits in vitro norovirus replication. Biochemical and Biophysical Research Communications 2012; 424: 777-780
  • 20 Sidwell RW. et al. Efficacy of orally administered T-705 on lethal avian influenza A (H5N1) virus infections in mice. Antimicrobial Agents and Chemotherapy 2007; 51: 845-851
  • 21 Wang M. et al. Remdesivir and chloroquine effectively inhibit the recently emerged novel coronavirus (2019-nCoV) in vitro. Cell Research 2020; 30: 269-271
  • 22 Furuta Y. et al. Favipiravir (T-705), a novel viral RNA polymerase inhibitor. Antiviral Research 2013; 100: 446-454
  • 23 Chen C et al. Favipiravir versus Arbidol for COVID-19: A Randomized Clinical Trial. medRxiv 2020; Preprint posted March 27, 2020
  • 24 Lipsitch M, Swerdlow DL, Finelli L Defining the epidemiology of Covid-19—studies needed. New England Journal of Medicine 2020; 382: 1194–1196
  • 25 Delang L, Abdelnabi R, Neyts J. Favipiravir as a potential countermeasure against neglected and emerging RNA viruses. Antiviral Research 2018; 153: 85-94
  • 26 Shiraki K, Daikoku T. Favipiravir, an anti-influenza drug against life-threatening RNA virus infections. Pharmacology & Therapeutics 2020; 107512
  • 27 Mendenhall M. et al. T-705 (favipiravir) inhibition of arenavirus replication in cell culture. Antimicrobial Agents and Chemotherapy 2011; 55: 782-787
  • 28 Avigan (favipiravir) Review Report. Pharmaceuticals and Medical Devices Agency, 2014
  • 29 Nagata T. et al. Favipiravir: a new medication for the Ebola virus disease pandemic. Disaster Medicine and Public Health Preparedness 2015; 9: 79-81