Oral Therapy Blocks Transmission of COVID-19

Previous studies with influenza in animals demonstrated antiviral efficacy was not species restricted.

Investigators working in the Institute for Biomedical Sciences at Georgia State University have discovered that the therapy Molnupiravir completely suppresses transmission of the SARS-CoV-2 virus within 24 hours. Prior research looked at how the therapy interacted with influenza viruses but has now led to the finding on the coronavirus disease 2019 (COVID-19).

"We noted early on that MK-4482/EIDD-2801 has broad-spectrum activity against respiratory RNA viruses and that treating infected animals by mouth with the drug lowers the amount of shed viral particles by several orders of magnitude, dramatically reducing transmission," Richard Plemper, lead author on the study said. "These properties made MK-4482/EIDD/2801 a powerful candidate for pharmacologic control of COVID-19."

The therapy is an antiviral and taken orally. Due to the fact that it is taken by mouth, patients will be able to receive it early on which will slow progress to a more severe stage of the disease. It will also quickly slow local outbreaks and shorten the infectious phase in recipients, lowering the emotional and socioeconomic toll associated with prolonged isolation.

The study, published in Nature Microbiology, looked at how Molnupiravir impacted ferrets and its effect on stopping the spread of the virus. Ferrets were infected with COVID-19 and immediately received the treatment. The antiviral was found to suppress all transmission to untreated direct contacts, while also observing that shed virions from the infected ferrets were only partially compromised. The therapy was well tolerated and reduced upper respiratory and gastrointestinal sample viral loads below the detection threshold within 24 hours of treatment.

"We believe ferrets are a relevant transmission model because they readily spread SARS-CoV-2, but mostly do not develop severe disease, which closely resembles SARS-CoV-2 spread in young adults," Robert Cox, co-lead author of the study said.

The team hopes that the data uncovered from the study will translate to human patients with the COVID-19 virus. The therapy would be a tremendous addition to the various other therapies that are being employed currently, slowing the spread of the disease significantly. Molnupiravir is currently in advanced phase II/III clinical trials against SARS-CoV-2 infections.