The anti-malarial drug hydroxychloroquine lowers the death rate of COVID-19 patients, U.S. researchers have said.
Researchers conducted a retrospective analysis of over 2,500 patients hospitalized between March 10 and May 2 in the Henry Ford Health System in Michigan. Over 2,000 of the patients were given hydroxychloroquine or the anti-malarial with azithromycin, an antibiotic.
Hydroxychloroquine alone decreased the mortality hazard ratio by 66 percent and the anti-malarial with the antibiotic decreased the ratio by 71 percent, researchers said.
The vast majority of patients were given the drug within 48 hours of admission.
“Our analysis shows that using hydroxychloroquine helped saves lives,” neurosurgeon Dr. Steven Kalkanis, senior vice president and chief academic officer of the health system, said in a statement. “As doctors and scientists, we look to the data for insight. And the data here is clear that there was benefit to using the drug as a treatment for sick, hospitalized patients.”
Patients who received hydroxychloroquine and azithromycin also had a lower mortality than people who received neither, as did patients who received azithromycin.
“The findings have been highly analyzed and peer-reviewed,” added Dr. Marcus Zervos, division head of Infectious Disease for Henry Ford, who co-authored the study with epidemiologist Dr. Samia Arshad.
“We attribute our findings that differ from other studies to early treatment, and part of a combination of interventions that were done in supportive care of patients, including careful cardiac monitoring," Zervos said. "Our dosing also differed from other studies not showing a benefit of the drug. And other studies are either not peer reviewed, have limited numbers of patients, different patient populations or other differences from our patients.”
None of the patients experienced side effects, researchers said, although patients who were monitored for a heart condition were recommended not to take the treatment.
The median age of patients was 64. The group was 51 percent male and 56 percent African-American.
The conclusions came from a peer-reviewed study that was published in the International Journal of Infectious Diseases.
Regardless of what treatment they received, mortality was highest in patients older than 65, patients who identified as Caucasian, patients admitted with reduced oxygen levels, and patients who required care in intensive care units, researchers said.
The results should be interpreted with some caution, Zervos said, and require further confirmation in randomized controlled clinical trials. Hydrxychloroquine should be used outside hospitals, he said.
It is no longer reasonable to believe that hydroxychloroquine and chloroquine may be effective in treating COVID-19, the agency's chief scientist, Denise Hinton, said.
Some of the trials pointed to side effects, including irregular heart rhythms, the agency warned.