May 18 (UPI) -- More than 50,000 healthcare workers worldwide will be enrolled in a clinical trial to assess chloroquine's potential in protecting against COVID-19, researchers at the Washington University of St. Louis School of Medicine announced Monday.
The U.S. arm of the study, which will begin enrolling participants later this month, is being led by the school. Results are expected in early 2021, researchers said.
"Because of their repeated close contacts with infected patients, frontline healthcare workers in all parts of the world have a higher risk of contracting COVID-19 than most members of the general public," principal investigator Michael S. Avidan, head of the Department of Anesthesiology at WUSTL, said in a press release.
"In some places, more than 10 percent of those who have become infected are healthcare workers. There is an urgent need to identify drugs that are effective at preventing infection or mitigating its severity," he added.
Officials at Rising Pharmaceuticals said Monday the company will be donating supplies of chloroquine, which is currently used to treat malaria, for the U.S. arm of the study. The research is being funded through the COVID-19 Therapeutics Accelerator, a partnership that includes the Bill and Melinda Gates Foundation, Wellcome and Mastercard.
Participants enrolled in the study will receive either 300 milligrams of chloroquine weekly, 300 mg. of the drug twice weekly, 150 mg. daily after being administered an "induction dose" of 1200 mg. chloroquine -- or placebo -- in four divided daily doses. New dosage arms may be added or removed as the trial progresses, according to the study design information filed with the U.S. Food and Drug Administration.
The goal of the study will be to determine which, if any, of the chloroquine regimens is most effective at decreasing incidence of severe COVID-19 -- the disease caused by the new coronavirus, SARS-CoV-2 -- without unacceptable side effects or safety events.
The hope is that the drug can prevent infection, or reduce the severity of symptoms, researchers said.
"When people have to travel to parts of the world where malaria is a problem, they often take low doses of chloroquine to help prevent infection," said Avidan, who is also a professor of psychiatry and surgery. "We want to learn whether this drug might work in a similar fashion in the case of COVID-19, or at the very least, whether low-dose chloroquine might help prevent the severe and life-threatening complications associated with the illness."
In addition to the United States, the trial will enroll healthcare workers from Canada, Mexico and various countries in Europe, Africa and South America, with a particular focus on lower- and middle-income countries. Because of shortages of healthcare workers in many of these countries, protecting them from severe COVID-19 is particularly important, the researchers said.