According to the study, published in the journal Nature Microbiology, the research team from Georgia State University (GSU) originally discovered that the drug is potent against influenza viruses.
"This is the first demonstration of an orally available drug to rapidly block SARS-CoV-2 transmission. MK-4482/EIDD-2801 could be game-changing," said study author Richard Plemper from GSU.
Because the drug can be taken by mouth, treatment can be started early for a potentially three-fold benefit: inhibit patients' progress to severe disease, shorten the infectious phase to ease the emotional and socio-economic toll of prolonged patient isolation and rapidly silence local outbreaks, "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," said Plemper.
"These properties made MK-4482/EIDD/2801 a powerful candidate for pharmacologic control of Covid-19," Plemper added.
In the study, the research team repurposed MK-4482/EIDD-2801 against SARS-CoV-2 and used a ferret model to test the effect of the drug on halting virus spread.
The team 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.
The researchers infected ferrets with SARS-CoV-2 and initiated treatment with MK-4482/EIDD-2801 when the animals started to shed virus from the nose.
"When we co-housed those infected and then treated source animals with untreated contact ferrets in the same cage, none of the contacts became infected," said study co-author Josef Wolf.
If these ferret-based data translate to humans, Covid-19 patients treated with the drug could become non-infectious within 24 hours after the beginning of treatment.
"MK-4482/EIDD-2801 is in advanced phase II/III clinical trials against SARS-CoV-2 infection," the authors wrote.