It is the second large, late-stage study to show that combination therapy of two antibodies, bamlanivimab and etesevimab, is effective at treating mild to moderate cases of Covid-19.

The previous study, which published data in January, used a higher dose of the drugs and reduced risk of hospitalisation by 70%.

“I expect this data to continue to drive more utilisation of the antibodies,” said Daniel Skovronsky, chief scientific officer at Eli Lilly.

“We have few other diseases where we have drugs that can offer this magnitude of benefit.”

US regulators authorised the combination therapy in February for use in Covid-19 patients 12 and over with a high risk of developing serious complications.

European regulators green lighted its use in March.

The US agreed in February to purchase a minimum of 100,000 doses of the combination treatment.

Regulators authorised bamlanivimab alone for use against Covid-19 last year and the US government agreed to purchase nearly 1.5 million doses.

Skovronsky said the combination therapy has the benefit of offering greater protection against new strains of Covid-19.

A variant of Covid-19 originally discovered in Britain has infected patients in most US states and is expected to become the country’s dominant strain.

“We are quite confident this combo covers all of the variants in the US,” Skovronsky said, adding Lilly is studying an additional treatment for new Covid strains first identified in South Africa and Brazil, which have not become widespread in the US.

Skovronsky said that Lilly is prepared to manufacture 1 million doses of the combination therapy in the coming months and is in active talks to supply governments around the world with the treatment.