COVID-19: Breakthrough treatment claims to stop 100% of symptomatic infections

The makers of an experimental drug, now being trialled by the NHS, say it is 100 per cent effective in protecting against symptomatic cases of the virus.

US-based Regeneron Pharmaceuticals says its two-antibody cocktail called REGEN-COV also reduces overall coronavirus infection rates by about 50 per cent.

The claims are based on interim results and the "confirmatory stage" of the trial will not be complete until the second quarter of this year, but the company has said it is hopeful it may "break the chain" of rising infections.

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George Yancopoulos, president and chief scientific officer at Regeneron, said even with the roll out of vaccines, hundreds of thousands of people are still infected with coronavirus daily who were then "actively spreading the virus to their close contacts.

"The REGEN-COV antibody cocktail may be able to help break this chain by providing immediate passive immunity to those at high risk of infection, in contrast to active vaccines which take weeks to provide protection," he added.

Regeneron analysed 400 participants in its trial, all of whom had a household member with COVID-19.

REGEN-COV works by combining two antibodies which bind to a protein on the surface of the virus and blocks infections of SARS-CoV-2, the virus that causes COVID-19.

Watch: Antibody cocktail could be used as passive vaccine, Regeneron says

Former US president Donald Trump claimed the drug "cured" him after he contracted COVID-19 last year.

The plan is to use the drug for people who need "immediate protection" such as those who have come into contact, or live with, someone who has tested positive.

But it is also for use in people who "respond poorly to vaccination" as it involves direct delivery of virus-fighting antibodies into the body, unlike traditional vaccines in which the receiver's immune system is activated to develop its own antibodies.

Oxford University's Randomised Evaluation of COVid-19 thERapY (RECOVERY) study - the world's largest clinical trial of hospitalised COBID-19 patients - is testing REGEN-COV.

RECOVERY'S studies focus on at least 2,000 patients in 174 UK hospitals.

The news comes as the UK passed the grim milestone of recording more than 100,000 deaths to the disease - and as the head of NHS England, Sir Simon Stevens, said he hoped more treatments would become available in the future.

He told Tuesday's Downing Street press conference: "Fundamentally the driver of the death rate is the infection rate, set against that we are seeing continuing improvements in hospital treatment for severely sick coronavirus patients."

Sir Simon added: "We do expect that there will be more treatments for coronavirus looking out over the next six to 18 months, perhaps.

"We've already seen those with some of the corticosteroids, some of the rheumatoid arthritis drugs that have been repurposed, there are antivirals in the pipeline.

"So, looking out, I think we can see a world in which coronavirus may be more treatable."

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