British researchers have found the first drug to improve survival of Covid-19 patients, in a breakthrough that was hailed by the chief medical officer.

Dexamethasone has been confirmed to reduce death by up to one third in hospitalised patients with severe respiratory complications of the virus. 

The low-cost, and widely available, steroid is typically used to treat inflammation, allergies and other breathing conditions such as asthma and COPD, among others.

It has now been approved for NHS use for Covid-19.

In March, the University of Oxford’s RECOVERY trial was established as a randomised clinical trial to test a range of potential treatments, with over 11,500 patients ultimately enrolled from over 175 NHS hospitals.

Results show that dexamethasone reduced deaths by a third in ventilated patients, and by one fifth in other patients receiving oxygen only. It did not benefit patients who did not require respiratory support.

In total, 2,104 patients were randomised to receive dexamethasone 6mg once per day, by mouth or intravenous injection, for ten days. They were compared with 4,321 patients randomised to usual care alone. Among those who received usual care alone, 28-day mortality was highest in those who required ventilation (41%), intermediate in those who required oxygen only (25%), and lowest among those who did not require any respiratory intervention (13%).

According to these results, one death would be prevented by treatment of around eight ventilated patients, or around 25 patients requiring oxygen alone.

Welcoming the information, chief trial investigator Professor Peter Horby said: ‘Dexamethasone is the first drug to be shown to improve survival in Covid-19.

‘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. Dexamethasone is inexpensive, on the shelf, and can be used immediately to save lives worldwide.’

Chief medical officer Professor Chris Whitty also heralded it as ‘the most important trial result for Covid-19 so far’, adding: ‘Significiant reduction in mortality in those requiring oxygen or ventilation from a widely available, safe and well known drug. Many thanks to those who took part and made it happen. It will save lives around the world’.

The full details will be published as soon as possible.