“The challenge came at Christmas when these new variants appeared – the South Africa and Brazil ones particularly. The changes the virus makes in its spike proteins actually throw off these antibodies,” he said.

“So basically, most of the front-running antibody therapies for Covid which are the front-running therapies for Covid, I should say – so the great hope – are lost to the South African and Brazilian variants.”

GlaxoSmithKline’s treatment still works against those variants, but not against the one that emerged in Kent in the UK. But with the coronavirus mutating as much as it has done already, Cammack does not expect any of the current drugs to to be effective for long.