A drug touted by US President Donald Trump as a treatment for Covid-19 has not benefit on hospitalised patients and could raise the risk of heart problems and death, according to a study of nearly 100,000 cases.
The conclusions were based on data from 671 hospitals on six continents, and released in a paper published in the peer-reviewed medical journal The Lancet on Friday, last week.
The study on the antimalarial hydroxychloroquine was released just days after Trump revealed he was taking the medication.
“I’m taking it for about a week and a half now and I’m still here, I’m still here,” he said last week.
The paper assessed the cases of 96,032 hospitalised patients, of whom 14,888 were treated with hydroxychloroquine, chloroquine, or a combination of the drugs with a class of antibiotics called macrolides.
There has not been a randomised trial on the use of hydroxychloroquine to treat Covid-19, but the study is the biggest and comprehensive of its kind on the drug so far.
“Although observational studies cannot fully account for unmeasured confounding factors, our findings suggest not only an absence of therapeutic benefit but also potential harm with the use of hydroxychloroquine or chloroquine drug regimens (with or without a macrolide) in hospitalised patients with Covid-19,” the paper said.
The authors said the drug regimens should not be used outside clinical trials and urgent confirmation from randomised clinical trials was needed.
The study was conducted by researchers from Harvard Medical School, health data firm Surgisphere, University Hospital of Zurich, the University of Utah and the HCA Research Institute.
All 14,888 people treated with the chloroquine regimens were given the medication within 48 hours of being diagnosed with Covid-19 and were not on mechanical ventilation when they started the treatment. The number of cases in each treatment ranged from 1,868 to 6,211. And the rest are in the control group.
After controlling for age, sex, race or ethnicity, underlying comorbidities, and disease severity at baseline, the patients who received these treatments were each independently associated with an increased risk of in-hospital mortality.
While the control group had a mortality rate of 9.3 per cent, the treatment groups had the death rate ranging from 16.4 per cent to 23.8 per cent.
In addition, the patients in the treatment groups reported a much higher percentage of heartbeat abnormalities known as de-novo ventricular arrhythmia.
Hydroxychloroquine or chloroquine, often combined with a macrolide, are the widely advocated regimens for Covid-19 based on laboratory studies of antiviral effects and some smaller uncontrolled studies.