Favipiravir versus Arbidol for COVID-19: A Randomized Clinical Trial

Chang Chen; Jianying Huang; Zhenshun Cheng; Jianyuan Wu; Song Chen; Yongxi Zhang; Bo Chen; Mengxin Lu; Yongwen Luo; Jingyi Zhang; Ping Yin; Xinghuan Wang

were reported, whilst some of them (Remdesivir, hINFa-2b, Ribavirin, Chloroquine and Arbidol) are currently under clinical trials for COVID-19. 3, 4 SARS-CoV-2 and influenza viruses exhibit similar disease presentations with similar organ trophism. Because both viruses are RNA virus depending on RNA-dependent RNA polymerase (RdRp) to replicate, the RdRp inhibitor Arbidol (common name for Umifenovir) approved for influenza in Russia and China has been proposed as a standard care option for COVID-19, mainly based on its mechanism-of-action (MoA) and its effects in treating influenza-associated pneumonia. [5] [6] [7] Favipiravir, an antiviral drug targeting RdRP, 8 approved in Japan for influenza, has an IC50 of 0.013-0.48 ug/ml for influenza A. Comparing this with the EC50 of 2.7-13.8 ug/ml of Arbidol, 9 we consider Favipiravir might serve as a potential candidate to treat COVID-19. Specifically, we hypothesized that Favipiravir would be superior to Arbidol in terms of improving clinical recovery rate at Day 7, and alleviating pyrexia, cough, and ARDS. To evaluate the clinical efficacy and safety of Favipiravir versus All rights reserved. No reuse allowed without permission. author/funder, who has granted medRxiv a license to display the preprint in perpetuity.