Middle East respiratory syndrome coronavirus (MERS-CoV) is the causative agent of a
severe respiratory disease associated with more than 2468 human infections and over 851
deaths in 27 countries since 2012. There are no approved treatments for MERS-CoV infection
although a combination of lopinavir, ritonavir and interferon beta (LPV/RTV-IFNb) is currently
being evaluated in humans in the Kingdom of Saudi Arabia. Here, we show that
remdesivir (RDV) and IFNb have superior antiviral activity to LPV and RTV in vitro. In mice,
both prophylactic and therapeutic RDV improve pulmonary function and reduce lung viral
loads and severe lung pathology. In contrast, prophylactic LPV/RTV-IFNb slightly reduces
viral loads without impacting other disease parameters. Therapeutic LPV/RTV-IFNb
improves pulmonary function but does not reduce virus replication or severe lung pathology.
Thus, we provide in vivo evidence of the potential for RDV to treat MERS-CoV infections
