RIO DE JANEIRO, BRAZIL – Six months after the outbreak of the worst pandemic in the 21st century, which has killed nearly half a million people worldwide, researchers in the United Kingdom claim to have found the first treatment able to prevent deaths from Covid-19: dexamethasone.
The steering committee of the Recovery clinical trial, conducted in the United Kingdom with over 11,000 patients, said on Tuesday that the drug reduces mortality among very critical patients, who need assisted breathing, and also among those who need oxygen. The drug has not shown benefits among patients with milder cases of Covid-19.
According to researchers, dexamethasone can prevent one in eight deaths among the most severe patients and save one life out of 25 among those who receive oxygen. These results are still preliminary, but those in charge of the study said they will soon publish them in a peer-reviewed scientific journal.
In every clinical trial, there is an independent expert committee, which reviews the provisional data and is tasked with discontinuing it should a drug be found to have benefits, so that it may start to be immediately administered to all patients. This was the case on the 8th day of the Recovery study, which is looking at several treatments for Covid-19 in over 11,000 patients in 175 hospitals in the UK.
Dexamethasone is a well-known drug – it was discovered in 1957 – and inexpensive. It is a corticosteroid with anti-inflammatory effects and an immune response suppressant used against severe allergic reactions and autoimmune diseases such as rheumatoid arthritis. The World Health Organization (W.H.O.) considers it an essential drug for any health system.
This arm of the British trial examined 2,104 infected patients randomly selected to be administered the drug. Their progression was compared to that of 4,321 patients who were administered the standard care for Covid-19. Mortality among those requiring assisted breathing stood at 41 percent, while among those requiring oxygen, the mortality rate stood at 25 percent. Among patients who did not require either of these interventions, the mortality rate stood at 13 percent. In the first type of patients, dexamethasone reduced mortality by one-third. In the second type, by one-fifth. In the less critical patients, no benefit was observed.
“Dexamethasone is the first drug that improves survival in Covid-19,” said Peter Horby, a researcher at Oxford University and one of the study’s coordinators. “Survival is highest among patients who need assisted breathing, so this drug should be administered to all patients in this condition. Dexamethasone is inexpensive, it is available and can be used right away to save lives around the world,” the researcher added in a press release issued by the institution.
“Although these results are preliminary, they are very clear: dexamethasone reduces the risk of death in patients with severe respiratory complications,” added Oxford physician Martin Landray, another of the trial’s authors. “It’s fantastic that the first treatment that proves to prevent deaths is available and affordable around the world,” he said.
These results are particularly positive because they come shortly after the trial’s authors announced that one of the formerly most promising potential treatments – hydroxychloroquine – has no positive effects on hospitalized patients. The British trial is also testing the efficacy of other treatments, including plasma from recovered patients.
Antoni Trilla, a doctor at the Barcelona Clinical Hospital and scientific advisor to the Spanish government, recommends caution. “After all the problems with other drugs, an extra measure of caution is required,” he says. “These are preliminary data; we should wait until we see the complete data published to decide,” he adds.
Dexamethasone treatment has been used for months in severe Covid-19 cases in Spain. “So far, it’s the only treatment we can say with clinical certainty that improves patients’ condition,” says Pilar Ruiz-Seco, deputy director of internal medicine at the Infanta Sofía hospital in Madrid. “However, before deifying corticosteroids [the class of drugs that includes dexamethasone], one must bear in mind that they have risks,” she says. Until now, this type of drug was contraindicated to fight viruses because it has been shown with other infections, such as MERS, that it increases viral replication, which is why the W.H.O. dismissed it in its Solidarity trial,” she explains.
In addition, this drug weakens the immune system, which increases the risk of infections by bacteria. “Using corticosteroids against a virus represents a paradigm shift, but it makes sense because it reinforces the theory that what actually kills in Covid-19 is the inflammatory component [the excessive immune response, such as the cytokine storm],” says Ruiz-Seco.
The Recovery’s preliminary results support other earlier studies that had found benefits in dexamethasone, including a retrospective study of about 400 patients conducted at the Puerta de Hierro Hospital in Madrid. This study, not yet independently peer-reviewed, shows that corticosteroids reduce mortality by 41 percent.
Another study, conducted in Spain before the pandemic and published in The Lancet Respiratory Medicine, points out that dexamethasone relieves severe lung inflammation caused by severe infections. “Despite these results, there is still a long way to go, for instance: to identify which patients should be given the drug, when and what dosage,” says Cristina Avendaño, president of the Spanish Society of Clinical Pharmacology and co-author of the first study.
Source: El País