A low-cost synthetic steroid has been found to reduce COVID-19 deaths by up to a third in what is being described as a "groundbreaking development" in the fight against the virus.
The British government announced on Tuesday that dexamethasone is to be used on COVID-19 patients "from this afternoon."
Dexamethasone was one of several drugs tested by the UK's Recovery trial between March and June.
More than 2,100 COVID-19 patients were treated with a low-dose of the steroid once per day for 10 days and results were compared with 4,321 patients receiving only the usual care.
Researchers found that dexamethasone reduced death by one-third in ventilated patients — those with severe respiratory complications due to the novel coronavirus — and by one fifth in other patients receiving oxygen only.
There was no benefit among those patients who did not require respiratory support and the trial did not involve any patients outside a hospital setting.
Peter Hornby, a professor of Emerging Infectious Diseases at the University of Oxford and one of the Chief Investigators for the trial, said that dexamethasone "is the first drug to be shown to improve survival in COVID-19," and that it should therefore "become standard care" in patients requiring oxygen treatment.
The UK Government's Chief Scientific Adviser, Sir Patrick Vallance also stressed that "it is particularly exciting as this is an inexpensive widely available medicine."
"This is a ground-breaking development in our fight against the disease," he added.
Health Secretary Matt Hancock said that the UK government has been stockpiling the drug since March after "we spotted the early signs" of its potential and that it now has 200,000 courses at its disposal.
"We're working with the NHS so that the NHS standard treatment for COVID-19 will include dexamethasone from this afternoon," he added.
The Recovery trial also studied the anti-malaria drug hydroxychloroquine, but discontinued its use "due to lack of efficacy."
The drug had been touted as a possible treatment against the deadly virus from as early as February by French epidemiologist Didier Raoult, but several studies have since cast doubt on its potential.
The United States' Food and Drug Administration (FDA) announced on Monday that it had revoked its Emergency Use Authorisation of chloroquine and hydroxychloroquine after clinical trial results led "BARDA [Biomedical Advanced Research and Development Authoity] to conclude that this drug may not be effective to treat COVID-19 and that the drug's potential benefits for such use do not outweigh its known and potential risks".