Malaria drugs pushed by President Donald Trump as treatments for Covid-19 have been proved to be ineffective according to a new report.
The drugs have now been shown to be tied to a greater risk of death and heart rhythm problems in the study of nearly 100,000 patients around the world.
The report in the journal Lancet is not a rigorous test of hydroxychloroquine or chloroquine, but it is by far the largest look at their use in real world settings, spanning 671 hospitals on six continents.
“Not only is there no benefit, but we saw a very consistent signal of harm,” said one study leader, Dr. Mandeep Mehra, a heart specialist at Brigham and Women’s Hospital in Boston.
Researchers estimate that the death rate attributable to use of the drugs, with or without an antibiotic such as azithromycin, is roughly 13 per cent versus 9 per cent for patients not taking them.
The risk of developing a serious heart rhythm problem is more than five times greater.
New England Journal of Medicine also published preliminary results of a study sponsored by the National Institutes of Health of remdesivir, a Gilead Sciences drug that is the first to show any evidence of benefit against the coronavirus in a large, rigorous experiment.
As previously announced, in a study of 1,063 patients sick enough to be hospitalised, the drug shortened the time to recovery by 31 per cent — 11 days on average versus 15 days for those just given usual care.
After two weeks, about 7.1 per cent of those on the drug had died versus 11.9 per cent of a comparison group given a placebo, but the difference was too small to say it could not have been due to chance.
Researchers will track the patients for another two weeks to see if death rates change over time.
The study of the malaria drugs was less rigorous and observational, but its size and scope gives it a lot of impact, said Dr. David Aronoff, infectious diseases chief at Vanderbilt University Medical Center.
President Trump repeatedly has pushed the malaria drugs, even admitting to taking hydroxychloroquine to try to prevent infection or minimise symptoms from the coronavirus.
The drugs are approved for treating lupus and rheumatoid arthritis and for preventing and treating malaria, but no large rigorous tests have found them safe or effective for Covid-19.