Co-administration of Favipiravir and the Remdesivir Metabolite GS-441524 Effectively Reduces SARS-CoV-2 Replication in the Lungs of the Syrian Hamster Model
S. Chiba, Maki Kiso, Noriko Nakajima, Shun Iida, Tadashi Maemura, Makoto Kuroda, Yuko Sato, Mutsumi Ito, Moe Okuda, Shinya Yamada, Kiyoko Iwatsuki‐Horimoto, Tokiko Watanabe, Masaki Imai, Tammy Armbrust, Ralph S. Baric, Peter Halfmann, Tadaki Suzuki, Yoshihiro Kawaoka
Abstract
During a pandemic, repurposing drugs that are approved for other diseases is a quick and realistic treatment option. In this study, we found that co-administration of favipiravir and the remdesivir metabolite GS-441524 more effectively blocked SARS-CoV-2 replication in the lungs of Syrian hamsters than either favipiravir or GS-441524 alone as part of a prophylactic or therapeutic regimen. Prophylactic co-administration also reduced the severity of lung inflammation. Moreover, co-administration of these drugs to naive hamsters efficiently protected them from airborne transmission of the virus from infected animals. Since both drugs are nucleotide analogs that interfere with the RNA-dependent RNA polymerases of many RNA viruses, these findings may also help encourage co-administration of antivirals to combat future pandemics.