Three new studies strongly support using inexpensive and widely available drugs to treat people who are seriously ill with COVID-19. The drugs are steroids, and the research published Wednesday confirms they are proving to be the most effective treatment found to date.

Initially, the use of these drugs in COVID-19 was controversial. Some doctors have long used steroids to treat conditions related to COVID-19, namely sepsis and acute respiratory distress syndrome.

Steroids help tamp down the immune system's potentially deadly overreaction to an infection. But some doctors worried that steroids could also prevent the body from fighting off the coronavirus effectively.

"Giving steroids to COVID-19 could have been quite scary," says Dr. Derek Angus, a critical care specialist at the University of Pittsburgh Medical Center.

In June, a major study from the U.K. found that the steroid dexamethasone was a big help. It reduced deaths significantly among the most serious cases of COVID-19 — notably people who needed ventilators or supplemental oxygen.

That advance was great news, but those findings created a conundrum for Angus and other researchers who were running their own studies of steroids in COVID-19 patients. It no longer felt appropriate to be giving some people steroids and others a placebo.

"Essentially overnight, because these findings were so striking, there was this sense among clinicians participating in other clinical trials [that] ... we have to stop our trials."

So those studies all ended prematurely. Researchers from three research groups have now published the findings they had gathered in the journal JAMA. One group is from France, one is from Brazil, and the third is an international team that includes the University of Pittsburgh's Angus.

Taken together, the publication of these studies "represents an important step forward in the treatment of patients with COVID-19," Drs. Hallie Prescott and Todd Rice wrote in a JAMA editorial. The results not only provide further support for the use of dexamethasone, they also back the use of another widely used steroid, hydrocortisone.

"I think it's good news to have a strong, clear signal on what is a widely available, inexpensive class of therapies," Angus says. He also contrasts these studies with a lot of other research on COVID-19. Many other studies, such as those involving much-hyped anti-malaria drugs, did not randomize their participants or include a comparison group. Such measures — randomized controlled trials — are the gold standard for medical research.

"It is reassuring that we can get randomized trials executed successfully and rapidly in the face of a pandemic," Angus says, "and it definitely puts us on a surer footing."

Based on these new results and related analysis, the World Health Organization on Wednesday updated its guidelines for steroids. It now recommends them for severely or critically ill COVID-19 patients, such as those on a ventilator, but not for patients with milder disease.

You can contact NPR science correspondent Richard Harris at[email protected].

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