RT Journal Article SR Electronic T1 Nelfinavir inhibits replication of severe acute respiratory syndrome coronavirus 2 in vitro JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.04.06.026476 DO 10.1101/2020.04.06.026476 A1 Norio Yamamoto A1 Shutoku Matsuyama A1 Tyuji Hoshino A1 Naoki Yamamoto YR 2020 UL http://biorxiv.org/content/early/2020/04/08/2020.04.06.026476.abstract AB In December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, Hubei Province, China. No specific treatment has been established against coronavirus disease-2019 (COVID-19) so far. Therefore, it is urgently needed to identify effective antiviral agents for the treatment of this disease, and several approved drugs such as lopinavir have been evaluated. Here, we report that nelfinavir, an HIV-1 protease inhibitor, potently inhibits replication of SARS-CoV-2. The effective concentrations for 50% and 90% inhibition (EC50 and EC90) of nelfinavir were 1.13 µM and 1.76 µM respectively, the lowest of the nine HIV-1 protease inhibitors including lopinavir. The trough and peak serum concentrations of nelfinavir were three to six times higher than EC50 of this drug. These results suggest that nelfinavir is a potential candidate drug for the treatment of COVID-19 and should be assessed in patients with COVID-19.