The full results of a UK trial of dexamethasone, published on Friday confirmed its life-saving benefits for ventilator-connected Covid-19 patients. Although they suggest it may cause harm, if given too soon.
A total of 2,104 hospitalized patients received daily doses of six milligrams of dexamethasone for up to 10 days, while another 4,321 received standard treatment, comparing death rates after 28 days.
Among respirator patients, the death rate was 29.3% in those who took dexamethasone, versus 41.4% in those who did not, according to the study's findings published in the New England Journal of Medicine.
In patients who received oxygen through less invasive means than respirators, the benefit was less since 23.3% of those who received dexamethasone died compared to 26.2% of those who were not medicated with the steroid.
However, there were no benefits among those who were not receiving oxygen at the time the study began.
In this case, 17.4% of those who took dexamethasone died, against 14% of those who did not, suggesting that the drug increased their risk of mortality.
This is because the drug works by suppressing the abnormal immune response that damages the body's organs, rather than attacking the virus.
In an interview with AFP in June, American scientist Anthony Fauci cautioned that dexamethasone should not be prescribed too soon in
covid-19 patients.
It had no effect, or perhaps suggesting a worsening of things from the beginning, said the White House medical adviser.
Fauci considered that this is perfectly compatible with the knowledge that at the beginning of the infection the immune system is needed to suppress the virus.
The research authors estimated that the drug's benefits depend on the right dose, at the right time, in the right patient.
They also indicated that for
covid-19, for patients requiring oxygen, the abnormal immune response seems to be more responsible for the damage than the advance of the virus itself in the body.
But they cautioned that this hypothesis should not apply to other viral respiratory diseases like SARS, MERS, and influenza, without further study.
Dexamethasone was adopted in the United Kingdom on June 16, the day the initial research results were announced and is also recommended by the United States National Institutes of Health.