The experimental coronavirus drug that Donald Trump is receiving is in use in a small number of UK hospitals, according to an Oxford University professor.

The US president was given an artificial antibody treatment at the White House on Friday after being diagnosed with Covid-19. He has since admitted to the Walter Reed national military medical centre.

Prof Peter Horby, who is part of Oxford University’s national Recovery trial, which aims to identify potential treatments for Covid-19, said “about three hospitals in the north” began using the drug last weekend. He said the drug was due to be rolled out to another 30 to 40 UK hospitals next week.

He told BBC Radio 4’s Today programme that the drug, REGN-COV2, was “very promising” and “very potent”.

“The class of drugs, these artificial antibodies, have been around for quite a while now, and they’ve been extensively used in inflammatory conditions and cancers, and they’re pretty safe and well understood, and so the technology is something that I think we have confidence in,” Horby said.

“This particular drug has probably been given to, I would think now, four or five hundred patients, mild or severe patients in different trials, and so far there’s been no worrying safety signals.

“In the laboratory, in cell cultures, it has a very strong effect against the virus, and there have been studies in artificial animals where it also shows benefits. So probably of the drugs that are available, it’s one of the most promising.”

Horby said a single dose of the treatment provided prolonged protection for a month to six weeks, making it “quite attractive for the older population”.

The antibody cocktail works by binding to a protein on the surface of the virus, which stops the virus from attaching to cells and replicating while allowing the immune system to attack it.

Trump has been given the drug alongside remdesivir, an antiviral treatment that has been shown to help some coronavirus patients recover faster.

His wife, Melania, and one ofhis closest aides also tested positive for Covid-19 on Friday.