Administering chloroquine or hydroxychloroquine to treat Covid-19 may be harming patients more than it is helping them, a large-scale study has found.
The study, published in the journal Lancet analysed data of patients admitted for Covid-19 in 671 hospitals across six continents.
The patients positively diagnosed for Covid-19 were hospitalised between December last year and April 2020.
Researchers behind the study were “unable to confirm a benefit” of hydroxychloroquine or chloroquine, when used alone or with an antibiotic for Covid-19, they reported in the Lancet.
Instead they found the regimens of chloroquine with or without antibiotic decreased survival in hospitalisation and increased the frequency of ventricular arrhythmia—a condition in which the heart is triggered into beating too fast, which prevents oxygen-rich blood from circulating to the brain and body, and likely result in cardiac arrest.
Forgotten for years
Chloroquine, an antimalaria drug long gone out of use in much of the world, grabbed headlines after it was claimed as treatment for patients with Covid-19.
Some regimen required it to be used with some antibiotics that inhibit the growth of bacteria.
More than 96,000 patients were included in the study.
The researchers categorised patients into four groups depending on whether they were administered chloroquine or hydroxychloroquine with or without antibiotic.
A total 14,888 patients fit into one of the four groups; the remaining 81,144 were used as control.
A total 10,698 patients died in hospital. But the researchers found the regimens that involved choloroquine with or without antibiotics were each “independently associated with an increased risk of in-hospital mortality.”
They were also associated with an “increased risk” of arrhythmia during hospitalisation.
The chloroquine treatment for Covid-19 followed widespread publicity of small and uncontrolled studies that have suggested combining chloroquine and azithromycin successfully cleared coronavirus replication.
In the wait for clinical trials and absence of alternatives, some governments like the US and China have okayed it and issued guidelines.
The Lancet study is not the first not find benefits of chloroquine for Covid-19 treatment.
One study of 368 men raised concern that use of hydroxychloroquine was associated with a greater hazard of death.
Another study involving 181 patients from France reported using the drug at 600mg per day was not associated with any “measurable clinical benefit” in Covid-19 patients.