The analysis is part of the RECOVERY (Randomised Evaluation of COVid-19 thERapY) trial which was established to test a range of potential therapies for COVID-19, including low-dose dexamethasone -- a steroid treatment.
The RECOVERY trial included over 11,500 patients, enrolled from more than 175 hospitals in the UK, noted a statement published by the University of Oxford on Tuesday.
In the trial, a total of 2,104 patients were randomised to receive dexamethasone six milligrammes once per day -- either by mouth or by intravenous injection -- for ten days, and were compared with 4,321 patients randomised to usual care alone.
Among the patients who received usual care alone, mortality was highest in those who required ventilation (41 per cent), intermediate in those patients who required oxygen only (25 per cent), and lowest among those who did not require any respiratory intervention (13 per cent), the scientists said.
They found that dexamethasone reduced deaths by one-third in ventilated patients, and by one fifth in other patients receiving oxygen only.
However, the researchers said there was no benefit from dexamethasone among the patients who did not require respiratory support.
Based on these results, the scientists believe that the drug could prevent nearly one death in the treatment of around eight ventilated patients, or around 25 patients requiring oxygen alone.
"Dexamethasone is the first drug to be shown to improve survival in COVID-19. This is an extremely welcome result," said Peter Horby, one of the chief investigators of the trial from the University of Oxford in the UK.
"The survival benefit is clear and large in those patients who are sick enough to require oxygen treatment, so dexamethasone should now become standard of care in these patients," Horby said.
The drug, according to the scientists, is inexpensive, on the shelf, and can be used immediately to save lives worldwide.
"These preliminary results from the RECOVERY trial are very clear --dexamethasone reduces the risk of death among patients with severe respiratory complications," said Martin Landray, another chief investigator of the trial from the University of Oxford.
"COVID-19 is a global disease – it is fantastic that the first treatment demonstrated to reduce mortality is one that is instantly available and affordable worldwide," Landray added.
However, the drug is banned in-competition by the World Anti-Doping Agency (WADA) but its usage is allowed out-of-competition if athletes have the requisite Therapeutic Usage Exemption (TUE).
Asian bronze-winning Indian javelin thrower Davinder Singh Kang is currently under provisional suspension after returning positive for the substance in an in-competition test conducted last year.
In 2017, Real Madrid star Sergio Ramos had tested positive for the drug during the Champions League but was let off after offering an apology for the team doctor's failure to disclose the medication he had taken.