Results are in from the first organized trials of drugs to treat Covid-19, but so far, there’s no cure.

As the new respiratory disease spread widely starting in January, doctors—first in China and then in the US, Italy, and France—all moved to test readily available drugs that are used for other purposes and are fairly safe. Now, just three months into the pandemic, the first medical results from organized trials—studies structured to measure whether a drug actually helps—are becoming public. We count three so far, all involving drugs with antiviral properties.

Patients who end up in the ICU are begging for whatever treatment they can get, and demand for drugs will skyrocket in the US. Not only is the number of confirmed cases now over 35,000, but this week twice that many or more will likely feel the onset of typical symptoms like cough, fever, and shortness of breath.

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So far, there is no approved medicine for Covid-19, so the main treatment for severe cases isn’t drugs at all—it’s oxygen therapy, ventilators that help people breathe, and supportive care. Some patients get standard antibiotics.

Overall, scores of drug studies are under way, checking the benefits of everything from vitamin C to Chinese traditional medicine. A list of trials compiled by CellTrials.org, a consultancy, found that doctors had registered over 250 Covid-19 studies, mostly in China, and were seeking to recruit 26,000 patients. It may be another month before some other large, important studies, like several involving the experimental antiviral remdesivir, made by the US company Gilead, are ready to report any findings.

Here are the facts about the drug studies published so far.

Chloroquine or hydroxychloroquine

The hype: President Donald Trump praised the malaria drug, saying it had shown “tremendous promise” against Covid-19. “I think it’s going to be very exciting,” he said. “I think it could be a game-changer, and maybe not.”