Current DateSeptember 19, 2021

Dexamethasone, the first drug effective against Covid-19

Dexamethasone, an inexpensive and common steroid, could save the lives of critically ill Covid-19 patients, according to the findings of Recovery, a large clinical trial conducted in Britain. The drug is the first to show a clear effect on mortality from the SARS-CoV-2 virus, which has killed more than 430,000 people worldwide. The steroid reduced the deaths of trial patients on artificial respirators by approximately one third due to a severe form of Covid-19.

“This is a surprising result,” said Kenneth Baillie, a doctor in intensive care at the University of Edinburgh in the United Kingdom who is on the steering committee of the Recovery Trial. “It will clearly have a significant impact at the global level. The results were announced in a press release on June 16, but the researchers say they will publish their results soon and will share them with regulators around the world.

The Recovery trial, launched in March, is one of the largest randomized controlled trials in the world to test potential treatments for the coronavirus. Nearly 2,100 study participants received dexamethasone at a moderate dose of 6 milligrams daily for 10 days, and their course was compared to that of approximately 4,300 patients who received standard care for Covid -19.

The effect of dexamethasone was most pronounced in critically ill patients on an artificial respirator. A lesser improvement was also seen in patients who received just oxygen: their risk of dying was reduced by 20%. The steroid, on the other hand, did not show any effect on mild cases of Covid-19, that is, patients who received no oxygen or ventilation.

Shortly after the results were released, the British government announced that it had immediately authorized the use of dexamethasone for patients hospitalized for Covid-19 who required oxygen or artificial respiration.

“This is a major step forward,” said Peter Horby, an infectious disease specialist at the University of Oxford, UK, and the lead researcher on the trial. The use of steroids to treat viral respiratory infections such as Covid-19 has been controversial. Steroid trials during the SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome) epidemics caused by related coronaviruses were not very successful, said Peter Horby. However, he said, given the wide availability of dexamethasone and some promising results from steroid studies in previous epidemics, the Recovery researchers felt it was important to test this treatment in a rigorous clinical trial.

Recommendations from the World Health Organization and many countries have warned against treating people infected with the coronavirus with steroids, and some specialists have expressed concern about the possible generalization of treatment with steroids . These drugs suppress the immune response, which could help patients whose lungs are devastated by an overworked immune system that manifests in severe cases of Covid-19. But the immune system must still remain functional to defend itself against the virus itself.

The Recovery trial suggests that at the doses tested, the benefits of dexamethasone outweigh the potential drawbacks. The study found no adverse effects from the treatment. “This steroid can be given to almost anyone,” says Peter Horby.

And the clinical picture of response to treatment – with greater effects on severe forms of Covid-19 but no effect on mild infections – corresponds to the idea that an overactive immune response is correlated with severe forms of the disease, says Anthony Fauci, director of the US National Institute of Allergies and Infectious Diseases. “When a patient is in such a critical condition that they are put on respiratory support, it is usually that they have an excessive inflammatory response, which contributes as much to morbidity as the virus itself.”

“Finding effective treatments like this will transform the impact of the Covid-19 pandemic on public health and the global economy,” Nick Cammack, manager of the “therapeutic accelerator for Covid, said in a statement. -19 ”at Wellcome, a British charitable organization for biomedical research. “Although this study suggests that dexamethasone only benefits in severe cases, countless lives will be saved worldwide.”

To date, the only drug that has demonstrated benefits for patients with Covid-19 in a large, randomized, controlled clinical trial is the antiviral remesivir. But although it does reduce the length of hospital stay, it has no statistically significant effect on mortality.

However, the amounts of remdesivir available are very small. Although the manufacturer – Gilead Sciences, California – has taken steps to increase production of this antiviral, it is currently only available for a small number of hospitals around the world. In addition, remdesivir is complex to administer: it requires daily injections for several days.

Dexamethasone, on the other hand, is a basic drug found in pharmacies around the world and available in tablet form – an advantage as cases of Covid-19 continue to increase in countries where the access to care is limited. “For less than 50 euros, you can treat eight patients and save a life,” said Martin Landray, an epidemiologist at Oxford University and another researcher in the Recovery trial.

These findings may also have implications for other respiratory illnesses, adds Kenneth Baillie. Steroid treatments are also controversial for acute respiratory distress syndrome. “The results on the Covid-19 encourage us to re-examine this closely, because the benefit in terms of mortality is very important,” explains Kenneth Baillie. “I think this treatment will affect patients far beyond Covid-19. “