June 3 (UPI) -- The World Health Organization has resumed its medical trials on hydroxychloroquine Wednesday, the same day a new study says the drug doesn't prevent coronavirus.
WHO paused the tests May 25 so they could undergo review by the Data Safety Monitoring Board.
"On the basis of the available mortality data, the members of the committee recommended that there are no reasons to modify the trial protocol," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said during a briefing Wednesday.
More than 3,500 patients in 17 countries were enrolled in clinical trials of hydroxychloroquine for COVID-19 treatment.
A study of 15,000 patients published in the Lancet last month said taking the drug doubled the risks of dangerous cardiac side effects that could lead to death. But that study was retracted by the authors on Thursday over questions of the validity of the data.
Tedros added that the drug is accepted as generally safe for use in patients with autoimmune diseases or malaria.
Hydroxychloroquine and related drug chloroquine, have been used as anti-malarial drugs for decades. Doctors have also prescribed them for lupus and rheumatoid arthritis.
Trump said he took hydroxychloroquine as a prophylactic for undetermined amount of time last month. A study showed that prescriptions for hydroxychloroquine and chloroquine rose by 2,000 percent from March 15 to 21, which spanned the time before and after Trump touted them as a "game changer."
On Wednesday, a study conducted by the University of Minnesota found that hydroxychloroquine doesn't help patients prevent COVID-19 infections.
The randomized trial -- results of which were published in The New England Journal of Medicine on Wednesday, found that 11.8 percent of people taking the drug became infected with COVID-19. Of those not taking the drug, 14.3 percent became sick, which researchers consider statistically insignificant.
"While we are disappointed that this did not prevent COVID-19, we are pleased that we were able to provide a conclusive answer," Dr. David Boulware, lead author of the study, told the Minneapolis Star Tribune.
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This story has been updated to reflect that a study published in The Lancet has been retracted.