UK Prime Minister Boris Johnson hailed research into dexamethasone as a "chink of light" against the COVID-19 pandemic but stressed that the treatment doesn't negate the need for social distancing rules.
Earlier on Tuesday, it was announced dexamethasone had been found reduce deaths in COVID-19 patients requiring oxygen assistance by up to a third.
The cheap, widely available steroid will now to be used in the standard care for hospitalised patients in Britain, the government announced.
Peter Horby, professor of emerging infectious disease at the University of Oxford, said the result from the clinical trial into dexamethasone "was really quite remarkable".
He stressed that benefits were only found in patients requiring oxygen assistance but that that "covers about 75% of patients in hospitals".
He also explained that if it were to be used on eight patients in that category, one life would be saved.
He estimated the cost of treating the eight patients at £40 (€45).
But as there were no benefits to patients not requiring oxygen assistance, it is "not a drug that you would use in the community or in outpatients".
Sir Patrick Vallance, the UK government's chief scientific adviser, also hailed the drug's cheapness and availability.
"This is a drug which can immediately be used across the world for this condition," he pointed out.
He warned however that "this drug doesn't stop you catching the disease, it doesn't stop you going into hospital with the disease" and that even when being treated with it " it's roughly one in eight who survive" so urged people not to relax their social distancing.
His call was echoed by Johnson who said that dexamethasone is providing the "first chink of light" and igniting hope that treatments could soon come online "that can make a big difference to mortality rates".
"None of that negates the importance of us continuing to follow the rules," he said, adding: "we've turned the tide on it [COVID-19 pandemic] but we haven't yet finally defeated it."
The Department of Health and Social Care has announced that a further 233 people had died from COVID-19 in the UK over the previous 24 hours — a sharp rebound from the 38 fatalities recorded on Monday. The death toll now stands at 41,969.
The number of confirmed cases has meanwhile risen by 1,279 to 298,136.