MINNEAPOLIS — An anti-malaria drug that doctors hoped would work against COVID-19, and that President Donald Trump championed and said he took himself, has failed to show any benefit in a second University of Minnesota trial.

Researchers compared outcomes of people with early symptoms of COVID-19 — with one group taking hydroxychloroquine and the other taking a non-medicating placebo — and found no difference in outcomes.

Death rates of 0.4 benefit were identical in the two comparison groups. Hospitalizations and persistent symptoms were slightly more common in the placebo group, but not by a statistically significant difference. Mostly mild side effects such as nausea or stomach problems were reported by 43 benefit of the patients taking the drug vs. 22 benefit taking the placebo.

The results were hardly what researchers hoped for back in early spring when they launched one of the nation’s first clinical trials of any drug for COVID-19, an infectious disease caused by exposure to a novel coronavirus. Few treatments of any kind have been proven to work against COVID-19.

“This is definitely not what we thought was going to happen,” said Dr. David Boulware, a leader of the trial and a University of Minnesota infectious disease physician.

This is the second trial result produced by the university, with the first being published in the New England Journal of Medicine and examining whether hydroxychloroquine prevented symptoms and illnesses in people who had already been likely exposed to the virus. That study also didn’t show a benefit.

Boulware said there had been some hope that zinc would boost the effectiveness of the drug, but neither study showed any improved benefit for patients who took that supplement.

Political controversies complicated both studies, with Trump championing hydroxychloroquine in advance of any studies proving that it worked against COVID-19. At the same time, some doctors warned of side effects.

Both perspectives slowed national online recruiting for the clinical trial — because some people believed it was too risky to take the drug while others believed it was so effective that they didn’t want to risk ending up in the placebo arm of the study.

“It turns out that neither perspective is true,” Boulware said. “It is a safe medicine, but it just didn’t work.”

Full results from a British study were released on Wednesday and showed no difference in deaths among hospitalized COVID-19 patients when they took hydroxychloroquine. Length of hospitalizations and the use of ventilators actually increased in the group taking the medication in that study.

That juxtaposed with a study of hospitalized patients out of Detroit showing that the drug offered a benefit.

The latest University of Minnesota trial results showed a slight benefit among people with early COVID-19 symptoms who were older, but there weren’t enough people in the study in this age group to be statistically significant, Boulware said.