An immunosuppressant drug frequently used in the treatment of multiple sclerosis and thyroid dysfunction has shown positive results in reducing the severity of COVID-19’s effects in hospitalized patients, the biotech company which makes it reports. Synairgen reported Monday that patients who received interferon beta were twice as likely to recover from COVID-19 than those in a placebo control group, in a trial of 101 patients at nine specialist hospital sites across the U.K. between March 30 and May 27. Recipients of the drug were 80 percent less likely to develop a more severe version of the disease while breathlessness was “markedly reduced,” the results showed. Three subjects in the study who received a placebo died; no one who received interferon beta did, the company reports. The results of the study are still awaiting peer reviews and publication. Synairgen’s share price more than doubled in early Monday trading on the news on London markets.

The news came the same day that the U.K. signed an agreement to buy 90 million doses of possible vaccines being developed by BioNtech and Pfizer, as well as the pharma firm Valneva. That’s in addition to the 100 million doses it has on order for the promising vaccine from Oxford University being developed with AstroZeneca.