The pattern is always the same: A research institute announces that it will be conducting tests on a promising medicine to treat COVID-19, media outlets jump on the story, medical experts — and sometimes even presidents — offer their thoughts, and then people storm pharmacies in search of what they believe to be the cure. Promoted by US President Donald Trump, the anti-malarial hydroxychloroquine has been found to be ineffective and potentially dangerous. Now, researchers are reporting promising results with the steroid dexamethasone.

First, the data must be verified. That step is often sobering for those who believe that a miracle treatment has been found. It will be determined in which situations the drug works most effectively — and what deadly side effects it might trigger.

What little information we have about dexamethasone and COVID-19 comes from a trial conducted in Britain. Scientists tested a number of previously approved drugs for their effectiveness against COVID-19. The study recorded data from more than 11,500 patients at 175 hospitals around the United Kingdom.

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'Lifesaving scientific breakthrough'

For the study, 2,104 patients were each given 6 milligrams of the synthetic steroid daily for 10 days. The control group for the test comprised 4,321 people.

Preliminary results from the unpublished trial suggest that dexamethasone could reduce deaths among patients with serious cases of COVID-19. Death rates among patients on ventilators dropped by one-third compared with the control group. The death rate among patients receiving oxygen but no artificial ventilation fell by one-fifth. Dexamethasone showed no effectiveness whatsoever when given to patients who did not require oxygen. UK officials have decided to immediately begin using dexamethasone to treat COVID-19 patients.

"This is great news, and I congratulate the government of the UK, the University of Oxford, and the many hospitals and patients in the UK who have contributed to this lifesaving scientific breakthrough," World Health Organization Director-General Tedros Adhanom Ghebreyesus said in a statement released by the WHO on Tuesday.

Dexamethasone's known uses

Inexpensive and widely available around the world, dexamethasone has long been used to treat inflammation of the skin (eczema) and joints (arthritis) and cerebral edema caused by brain tumors, as well as to prevent nausea and vomiting as a result of cancer treatment.

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The immune system often overreacts in patients with serious cases of COVID-19. Dexamethasone is a strong and effective synthetic corticoid that suppresses such reactions and curbs inflammation.

The Randomized Evaluation of COVID-19 Therapy (RECOVERY) study conducted by Oxford has not been published in a journal, nor has it been peer-reviewed. Instead, participating British scientists announced the results of the trials on www.recoverytrial.net.

Response in Germany

German doctors have voiced cautious optimism. "The results fit our own current understanding that immune system overreactions play a major role in late-stage COVID-19 illness. The results — the full publication of which we are still waiting for — suggest use of cortisone preparations in severe cases of SARS-CoV-2 infection," said Gerd Fätkenheuer, head of the infectious diseases department at the University Hospital Cologne.

Maria J.G.T. Vehreschild, head of the infectious diseases department at Frankfurt's Goethe University Hospital, had a similar take. "Cortisone is a classic treatment approach to suppressing the immune system," she said. "But the proven effectiveness is surprising." However, Vehreschild added: "I have yet to see the original data. One won't be able to ultimately determine the quality of the findings until that data has been thoroughly studied."

Clemens Wendtner, the chief physician for infectious disease and tropical medicine at Munich's Schwabing hospital, cautioned against using dexamethasone as a preventative or administering it to patients with mild symptoms, saying it should only be given to patients with severe symptoms and in need of hospitalization. He did encourage the "earliest possible use of antiviral drugs like remdesivir on nonventilated patients to reduce virus load in the body and steroids for COVID-19 patients on ventilators to reduce the risk of serious lung infection."

Bernd Salzberger, the president of the German Society of Infectious Diseases , also noted the different uses of remdesivir and dexamethasone. "Remdesivir fights the virus," he said. "Dexamethasone fights overactive inflammation."

Though dexamethasone may turn out to be an effective treatment against COVID-19, the coronavirus pandemic remains the larger problem. "In light of the small, albeit significant, reductions in mortality rates through the use of steroids, the best medicine for stopping COVID-19 illness remains an efficient vaccine," Wendtner said.

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