THE world's first coronavirus treatment has been approved for use in the UK.

The steroid Dexamethasone is said to reduce the risk of death in people with coronavirus by 35%, and has been approved to treat all UK Covid-19 patients in hospital who need oxygen.

Peter Horby, Chair of the NERVTAG advisory group and a professor of emerging infectious diseases at the University of Oxford, said the results of trials using the steroid were "quite remarkable".

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He described the treatment as "an old drug... Some people would say it's a very boring drug, it's been around for 60 odd years" but added it had worked well in trials which have taken place in 175 hospitals across the country.

Mr Horby, who was involved in leading the trials, said it proved effective in some of the most at-risk patients, those in hospital on ventilators, and was found to reduce their risk of dying by 35%.

People who were in hospital needing oxygen, but who were not ventilated, had a reduced risk of 20%.

He explained: "There's another group of patients who don't require oxygen but have Covid. We did not see a benefit in those patients so it's not a drug that you would use in the community, or in outpatients or inpatients on the ward who didn't have breathing difficulties."

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The scientist added that it would cost around £5 per person, and people would either take it orally or by injection for 10 days.

Boris Johnson spoke about the treatment at this evening's Downing Street briefing, where he praised scientists for their work.

He said: "I'm absolutely delighted that the biggest breakthrough yet has been made by a fantastic team of scientists, right here in the UK.

" I am proud of these British scientists, backed by UK government funding, who led the first robust clinical trial, anywhere in the world to find a Coronavirus treatment proven to reduce the risk of death, and I'm very grateful to the thousands of patients in this country who volunteered for the trials. Thank you."

The Prime Minister added: "Of course, while the chances of dying from Covid-19 have been significantly reduced by this treatment, they are still far too high. So we must redouble our research efforts and we certainly will.

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"But today, there is genuine cause to celebrate a great, British achievement and the benefits it will bring not just in this country but around the world."

At the Holyrood briefing earlier today, Interim chief medical officer Dr Gregor Smith, said about the drug: "Certainly it has a role in some patients, maybe not all, but for many in terms of how we mediate and reduce the extreme elements of the inflammatory response.

"We await further confirmation of the outcome of that trial, and will consider that.

"We are currently working with the DHSC in England to see how we will use the dexamethasone that's available in the UK for that purpose."