A drug given to dogs to treat their cancer could be used to thwart Covid, scientists say.
Masitinib has been used on canines for over a decade — but is not yet approved for humans.
Academics already believe it may have potential in treating skin cancer, Alzheimer's, asthma and multiple sclerosis.
But now University of Chicago researchers hope it could also offer hope in the fight against the coronavirus pandemic.
Laboratory trials of masitinib — which costs just £2 a pill — found it stopped the virus replicating, which is how it ends up causing disease.
Studies showed it worked just as well against variants, and other similar viruses that can make humans ill.
But the trials were not carried out on humans, with the claims based solely on tests of the drug on mice and cell cultures.
The team are now planning human trials, in the hope it will be proven to work — and they are confident it will.
Professor Savas Tay, who led the research, said: 'Inhibitors of the main protease of SARS-CoV-2, like masitinib, could be a new potential way to treat Covid patients, especially in early stages of the disease
'Covid will likely be with us for many years, and novel coronaviruses will continue to arise.
'Finding existing drugs that have antiviral properties can be an essential part of treating these diseases.'